Phone Help - Google Pixel

Why is there no LED showing at all?
Try going into your phone settings -> notifications -> press the cog-> and and make sure "Pulse notification Light" is switched on.

Why is there a permanent notification in the pulled down notification bar when there wasn't on previous phones?
Any app that targets Android 6 (i.e. uses android 6 features such as run-time permissions, standard flash control etc) needs to build the app for Android 6 devices.

Google changed notifications in Android 6 so that notifications cannot be raised without a notification icon. As the LED is part of what Android classes as a notification the icon must exist for the LED to be able to show and for Light Flow to keep control of the LED.

I've raised a feature request with Google to improve LED control in future versions. It can be "starred" here https://code.google.com/p/android/issues/detail?id=190997 but please don't comment.

Why do I sometimes for a small amount of time see a notification in the notification bar?
When the screen is off Light Flow needs to have a notification set with a priority that allows the LED to show. The priority level of notification that allows this requires a notification to show in the notification bar at the top. When the screen switches on the app detects this and changes the priority of the notification, but sometimes depending on timings of other events taking place on the phone it may take a split second to change.

When Light Flow is on my Ambient display keeps triggering
This is a known issue, as the LED is part of android's notifications the ambient display detects an outstanding notification and switches on the screen. Sometimes this can happen quite frequently. The only solution to stop this at the moment is to switch off the ambient display in your phone settings->display->ambient display. I've raised a feature request with google to try and improve this.

It can be "starred" here https://code.google.com/p/android/issues/detail?id=191786, but please don't comment.




Android 6.0 general changes blog entry:


Phone Help - Google Pixel XL

Why is there no LED showing at all?
Try going into your phone settings -> notifications -> press the cog-> and and make sure "Pulse notification Light" is switched on.

Why is there a permanent notification in the pulled down notification bar when there wasn't on previous phones?
Any app that targets Android 6 (i.e. uses android 6 features such as run-time permissions, standard flash control etc) needs to build the app for Android 6 devices.

Google changed notifications in Android 6 so that notifications cannot be raised without a notification icon. As the LED is part of what Android classes as a notification the icon must exist for the LED to be able to show and for Light Flow to keep control of the LED.

I've raised a feature request with Google to improve LED control in future versions. It can be "starred" here https://code.google.com/p/android/issues/detail?id=190997 but please don't comment.

Why do I sometimes for a small amount of time see a notification in the notification bar?
When the screen is off Light Flow needs to have a notification set with a priority that allows the LED to show. The priority level of notification that allows this requires a notification to show in the notification bar at the top. When the screen switches on the app detects this and changes the priority of the notification, but sometimes depending on timings of other events taking place on the phone it may take a split second to change.

When Light Flow is on my Ambient display keeps triggering
This is a known issue, as the LED is part of android's notifications the ambient display detects an outstanding notification and switches on the screen. Sometimes this can happen quite frequently. The only solution to stop this at the moment is to switch off the ambient display in your phone settings->display->ambient display. I've raised a feature request with google to try and improve this.

It can be "starred" here https://code.google.com/p/android/issues/detail?id=191786, but please don't comment.




Android 6.0 general changes blog entry:


Phone Help Nexus6P

Why is there no LED showing at all?
Try going into your phone settings -> sounds and notifications -> and make sure "Pulse notification Light" is switched on.

Why is there a permanent notification in the pulled down notification bar when there wasn't on previous phones?
Any app that targets Android 6 (i.e. uses android 6 features such as run-time permissions, standard flash control etc) needs to build the app for Android 6 devices.

Google changed notifications in Android 6 so that notifications cannot be raised without a notification icon. As the LED is part of what Android classes as a notification the icon must exist for the LED to be able to show and for Light Flow to keep control of the LED.

I've raised a feature request with Google to improve LED control in future versions. It can be "starred" here https://code.google.com/p/android/issues/detail?id=190997 but please don't comment.

Why do I sometimes for a small amount of time see a notification in the notification bar?
When the screen is off Light Flow needs to have a notification set with a priority that allows the LED to show. The priority level of notification that allows this requires a notification to show in the notification bar at the top. When the screen switches on the app detects this and changes the priority of the notification, but sometimes depending on timings of other events taking place on the phone it may take a split second to change.

When Light Flow is on my Ambient display keeps triggering
This is a known issue, as the LED is part of android's notifications the ambient display detects an outstanding notification and switches on the screen. Sometimes this can happen quite frequently. The only solution to stop this at the moment is to switch off the ambient display in your phone settings->display->ambient display. I've raised a feature request with google to try and improve this.

It can be "starred" here https://code.google.com/p/android/issues/detail?id=191786, but please don't comment.

Some colors don't seem to display correctly
This seems to be a driver limitation issue. Colors such as Orange and Light pink don't seem possible.
LED colors are made up from the 3 seperate LEDS (red, green and blue).
It seems that once the brightness level is set on for example red and green then they are both set to the same brightness regardless of what the app sets for the brightness.

So for example setting Red to full brightness and Green to full brightness creates Yellow - which is correct.

Orange would generally be set by setting the Red to full brightness and the Green to 1/2 brightness, but it seems the LED drivers ignore this and just set both values the same - which causes orange to also show as yellow. I've raised an issue with Google for this here:
https://code.google.com/p/android/issues/detail?id=193187, please "star" the issue but please don't comment.


Android 6.0 general changes blog entry:
See here: http://www.reactle.com/2015/10/changes-for-android-6-marshmallow.html

Phone Help Nexus5X

Why is there no LED showing at all?
Try going into your phone settings -> sounds and notifications -> and make sure "Pulse notification Light" is switched on.

Why is there a permanent notification in the pulled down notification bar when there wasn't on previous phones?
Any app that targets Android 6 (i.e. uses android 6 features such as run-time permissions, standard flash control etc) needs to build the app for Android 6 devices.

Google changed notifications in Android 6 so that notifications cannot be raised without a notification icon. As the LED is part of what Android classes as a notification the icon must exist for the LED to be able to show and for Light Flow to keep control of the LED.

I've raised a feature request with Google to improve LED control in future versions. It can be "starred" here https://code.google.com/p/android/issues/detail?id=190997 but please don't comment.

Why do I sometimes for a small amount of time see a notification in the notification bar?
When the screen is off Light Flow needs to have a notification set with a priority that allows the LED to show. The priority level of notification that allows this requires a notification to show in the notification bar at the top. When the screen switches on the app detects this and changes the priority of the notification, but sometimes depending on timings of other events taking place on the phone it may take a split second to change.

When Light Flow is on my Ambient display keeps triggering
This is a known issue, as the LED is part of android's notifications the ambient display detects an outstanding notification and switches on the screen. Sometimes this can happen quite frequently. The only solution to stop this at the moment is to switch off the ambient display in your phone settings->display->ambient display. I've raised a feature request with google to try and improve this.

It can be "starred" here https://code.google.com/p/android/issues/detail?id=191786, but please don't comment.

Some colors don't seem to display correctly
This seems to be a driver limitation issue. Colors such as Orange and Light pink don't seem possible.
LED colors are made up from the 3 seperate LEDS (red, green and blue).
It seems that once the brightness level is set on for example red and green then they are both set to the same brightness regardless of what the app sets for the brightness.

So for example setting Red to full brightness and Green to full brightness creates Yellow - which is correct.

Orange would generally be set by setting the Red to full brightness and the Green to 1/2 brightness, but it seems the LED drivers ignore this and just set both values the same - which causes orange to also show as yellow. I've raised an issue with Google for this here:
https://code.google.com/p/android/issues/detail?id=193187, please "star" the issue but please don't comment.

Why can't I set the LED to be always on?
Again this seems to be an LED driver issue. It's been common on most recent LG phones (Nexus 5, LG G4 etc) that the LED drivers won't accept always on timings. Light Flow therefore allows setting the LED to "nearly always on" where it will slowly flash but mostly be on.


Android 6.0 general changes blog entry:
See here: http://www.reactle.com/2015/10/changes-for-android-6-marshmallow.html


Phone Help Nexus 6

Does the Nexus 6 have any notification lights?
It's not been advertised as having any, but it does have Red, Green and Blue leds (which can be mixed for more colors) but your phone will need root as Google didn't provide any direct access to them from within Android.

Files for rooting can be found here: http://autoroot.chainfire.eu/ - note we have no association with that site, but it's one of the most popular methods for rooting the phone.

Once rooted, go into light flow and select the following

Setting->Device settings and root

Enable the following options

- Direct Mode
- Root mode
- Run every command as root


Once these are set the app can gain access to the LEDs.

To enable the leds for a notification, go into light flow -> Notification settings.

To get the best control of the led, go to the "Light" tab and choose the "Enable mixer" option.

With this you can set up the Red, Green and Blue leds and their brightness


You'll need to select the "Solid" option in the Red LED, Green LED and Blue LED sections for the colors you want to use.

Then you can set a brightness of the led. This can be set between 1 and 20 with 1 being the dimmest and 20 being the brightest.


I keep getting a message that supersu has granted access to lightflow.
There's 2 ways to stop this, go into supersu and switch off their notifications for lightflow.
The other option is to download https://play.google.com/store/apps/details?id=com.mrbimc.selinux set permissive mode and then switch off "run every command as root" in lightflow

I don't want to root, can I still access the LEDs?
Sadly not, it's the only way to control the drivers. I do plan to try add a screen based notification led in the future

The LED is always on and won't flash?
At the moment it doesn't seem like the drivers allow this

Will the LED being always on drain the battery faster?
LED's such as the notification LED use very little battery and you shouldn't notice a drain from having them on.



Phone Help LG G3

I can't get the app to work, can you help?-
The most common issue is the phone settings, try going into your phone settings, LEDs and make sure only "downloaded apps" is switched on and all the other options are switched off, this will usually fix most issues.

If that doesn't fix it, try the steps below:


Go into your phone settings->security, notification access and switch off and back on light flow in the list. 

For all versions then
Go into your phone settings->apps(or applications)->select light flow and make sure "show notifications" is checked.
Go into your phone settings->display. Make sure your notification leds are enabled.


Switch off your phone with the power button.
Then switch it on again. Go into lightflow -> general settings and make sure direct mode is off.
Then go into notifications -> missed calls.
Set the color to "red"
Set the flash speed to "fast"
Press "test" Switch off your screen and wait 10 seconds.

Does the LED light up?

If not, try getting a real missed call as sometimes the test option is less reliable than the real notifications.

If it still doesn't work, try to disable and then re-enable the notification and repeat the test. If that doesn't work, can you go into your phone settings, apps, choose lightflow and select "clear data" and see if that helps.

Other devices

There are varying degrees of success with other devices.

Try the following to see if the app works:

If you are on android 4.2 or below:
Go into your phone settings->accessibility and switch off and back on lightflow in the list.

If you are on android 4.3 or above:
Go into your phone settings->security->notification access and switch off and back on light flow.

For all android versions:
Go into your phone settings->display. Make sure "pulse notification light" is checked (if the option exists - you may have something like LED's or Lights instead)
Switch off your phone with the power button. Then switch it on again.
Go into lightflow -> general settings and make sure direct mode is off.
Then go into notifications -> missed calls.
Set the color to "red"
Set the flash speed to "fast"
Press "test"
Switch off your screen and wait 10 seconds.
Does the LED light up?

Phone Help Sony Xperia SP


Light Flow only controls the one central LED on the illumination bar, can it control all 3?
Yes it's possible to control all 3. Go into lightflow -> settings -> Led Control

Switch off "Main LED Control" and switch on "Illumination bar"

Then for each notification lightflow will use the new illumination bar option instead of the default color setting. This option allows for all three leds to be on and also allows for control when the screen is off.

The led does not work, what can you suggest?
Firstly make sure stamina mode (or extended battery mode) is disabled as this will kill any 3rd party services running in the background (including light flow)
Go into your phone settings->accessibility and switch off and back on lightflow in the list.
Check if there's a setting in your phone settings->display. If there's one regarding the led/light make sure it's on. (don't worry if it's not there)
Switch off your phone with the power button. Then switch it on again.
Go into lightflow -> general settings and make sure direct mode is off.
Then go into notifications -> missed calls.
Set the color to "red"
Set the flash speed to "fast"
Press "test"
Switch off your screen and wait 10 seconds.
Does the LED light up?

If that doesn't work, can you go into your phone settings, apps, choose lightflow and select "clear data" and see if that helps.





Phone Help Nexus 5

What settings do I need to test the app on the nexus 5?
Go into your phone settings->security, notification access and switch off and back on light flow in the list.

Go into your phone settings->apps->select light flow and make sure "show
notifications" is checked.
Go into your phone settings->display. Make sure "pulse notification light" is checked.

Switch off your phone with the power button. Then switch it on again.
Go into lightflow -> general settings and make sure direct mode is off.
Then go into notifications -> missed calls.
Set the color to "red"
Set the flash speed to "fast"
Press "test"
Switch off your screen and wait 10 seconds.
Does the LED light up?

If not, try getting a real missed call as sometimes the test option is less reliable than the real notifications.

If it still doesn't work, try to disable and then re-enable the notification and repeat the test.

If that doesn't work, can you go into your phone settings, apps, choose light flow and select "clear data" and see if that helps.

Why do I sometimes for a small amount of time see a notification in the notification bar on android 6.0?
When the screen is off Light Flow needs to have a notification set with a priority that allows the LED to show. The priority level of notification that allows this requires a notification to show in the notification bar at the top. When the screen switches on the app detects this and changes the priority of the notification, but sometimes depending on timings of other events taking place on the phone it may take a split second to change.

Hangouts doesn't work for sms correctly
Make sure you are on version 3.14.101 or greater of the app for these to work
Note in version 3.14.101 for sms to work you'll also need "hangouts - all notifications" enabled as well as "sms apps". This dependency isn't required in later versions.

After a phone call the led is still on when the screen is on / the led flashes red/green/blue quickly after a call
This seems to be a bug on the nexus 5 or in android 4.4 (kitkat). I've put a workaround in, but it'll only fire once the screen is off as android ignores led controls make when the screen is on. Note you'll get a quick red,green,blue flash after calls to and for the 1st subsequent notification to reset the led to working again.


"Always on" flash speed doesn't work
The drivers don't support always on so the app's had a small change to have an "almost always on" settings instead which seems to be the best the LED driver can support.

Phone Help Nexus 10

 

Phone Help Nexus 7

 

Phone Help Moto X

 

Phone Help Samsung Note 3

 My phone has updated to android 5.1.1 and now I just get a blue led.
See here for details of a workaround for this issue: http://www.reactle.com/2015/07/samsungled.html

I've updated to Android 5 (lollipop) and now my leds don't work
Try going into your phone settings, display, led indicators and make sure that "notifications" is enabled and everything else is switched off. 

Also note that on android 5/Lollipop that the led won't show when the phone is in silent/mute mode due to changes make by google and samsung. Once android 5.1 comes to the phone it should start working again if samsung make the same changes Google have on their nexus devices.

How do I set up my phone to get notification LEDs from Light Flow?

Go into your phone settings, accessibility and switch off light flow
Then go into your phone settings, security, notification access and switch on lightflow

Go into your phone settings->application manager->select light flow and make sure "show notifications" is checked.
Then restart your phone (ie power it off and back on)
Go into your phone settings, display, led indicators and make sure only "notifications" is checked.
Go into lightflow, settings and make sure all of the following are off (they should be by default):
      Direct mode
      Samsung root mode
      USA/Canada S3 mode.
Then go into lightflow, notifications, missed call and select the color red.
Press the phones "home" key and switch off the screen.
Then try get a missed call and see if the led flashes red.
If that works, then settings other notifications on should generally work. 


When I try to switch on the accessibility service the phone warns me that it's going to switch off features such as Air View, Air gesture and a few others. Why do these need to be switched off?
They don't, and most can be switched straight back on once light flow is installed. It's a bug in Samsung's accessibility service which causes this.

Phone Help Samsung Note 2

 

Phone Help Samsung Galaxy S3 mini

Sadly the s3 mini doesn't have a notification LED in its hardware.

You can still use the app for it's other features such as


  • Repeating sounds and notifications
  • Sending vibration patterns to android wear watches
  • Settings up sleep times and exceptions for notifications
  • Flashing the screen when notifications arrive
  • Repeating screen flashing

Phone Help Samsung Galaxy S4 mini

 

Phone Help Samsung Galaxy S5 and S5 mini

My phone has updated to android 5.1.1 and now I just get a blue led.
See here for details of a workaround for this issue: http://www.reactle.com/2015/07/samsungled.html

I've updated to Android 5 (lollipop) and now my leds don't work
Try going into your phone settings, display, led indicators and make sure that "notifications" is enabled and everything else is switched off. 

Also note that on android 5/Lollipop that the led won't show when the phone is in silent/mute mode due to changes make by google and samsung. Once android 5.1 comes to the phone it should start working again if samsung make the same changes Google have on their nexus devices.

How do I set up my phone to get notification LEDs from Light Flow?

Go into your phone settings, accessibility and switch off light flow
Then go into your phone settings, security, notification access and switch on lightflow

Go into your phone settings->application manager->select light flow and make sure "show notifications" is checked.
Then restart your phone (ie power it off and back on)
Go into your phone settings, display, led indicators and make sure only "notifications" is checked.
Go into lightflow, settings and make sure all of the following are off (they should be by default):
      Direct mode
      Samsung root mode
      USA/Canada S3 mode.
Then go into lightflow, notifications, missed call and select the color red.
Press the phones "home" key and switch off the screen.
Then try get a missed call and see if the led flashes red.
If that works, then settings other notifications on should generally work. 


When I try to switch on the accessibility service the phone warns me that it's going to switch off features such as Air View, Air gesture and a few others. Why do these need to be switched off?
They don't, and most can be switched straight back on once light flow is installed. It's a bug in Samsung's accessibility service which causes this.

Phone Help Samsung Galaxy S4

My phone has updated to android 5.1.1 and now I just get a blue led.
See here for details of a workaround for this issue: http://www.reactle.com/2015/07/samsungled.html

I've updated to Android 5 (lollipop) and now my leds don't work
Try going into your phone settings, display, led indicators and make sure that "notifications" is enabled and everything else is switched off. 

Also note that on android 5/Lollipop that the led won't show when the phone is in silent/mute mode due to changes make by google and samsung. Once android 5.1 comes to the phone it should start working again if samsung make the same changes Google have on their nexus devices.

How do I set up my phone to get notification LEDs from Light Flow?

Go into your phone settings, accessibility and switch off light flow
Then go into your phone settings, security, notification access and switch on lightflow

Go into your phone settings->application manager->select light flow and make sure "show notifications" is checked.
Then restart your phone (ie power it off and back on)
Go into your phone settings, display, led indicators and make sure only "notifications" is checked.
Go into lightflow, settings and make sure all of the following are off (they should be by default):
      Direct mode
      Samsung root mode
      USA/Canada S3 mode.
Then go into lightflow, notifications, missed call and select the color red.
Press the phones "home" key and switch off the screen.
Then try get a missed call and see if the led flashes red.
If that works, then settings other notifications on should generally work. 


When I try to switch on the accessibility service the phone warns me that it's going to switch off features such as Air View, Air gesture and a few others. Why do these need to be switched off?
They don't, and most can be switched straight back on once light flow is installed. It's a bug in Samsung's accessibility service which causes this.

Phone Help Samsung Galaxy S3

How do I set up my phone to get notification LEDs from Light Flow?

Go into your phone settings, accessibility and switch off light flow
Then go into your phone settings, security, notification access and switch on lightflow

Go into your phone settings->application manager->select light flow and make sure "show notifications" is checked.
Then restart your phone (ie power it off and back on)
Go into your phone settings, display, led indicators and make sure only "notifications" is checked.
Go into lightflow, settings and make sure all of the following are off (they should be by default):
      Direct mode
      Samsung root mode
      USA/Canada S3 mode.
Then go into lightflow, notifications, missed call and select the color red.
Press the phones "home" key and switch off the screen.
Then try get a missed call and see if the led flashes red.
If that works, then settings other notifications on should generally work. 


When I try to switch on the accessibility service the phone warns me that it's going to switch off features such as Air View, Air gesture and a few others. Why do these need to be switched off?
They don't, and most can be switched straight back on once light flow is installed. It's a bug in Samsung's accessibility service which causes this.

Phone Help Sony Xperia phones

Do you support the Illumination bar?
From version 3.15.100 of the app upwards, yes.
There's support for the following phones
Xperia™ SP
Xperia™ ZL
Xperia™ ZR
Xperia™ UL
Xperia™ A
Xperia™ U
Xperia™ L
Xperia™ S (only white led in hardware)
Xperia™ SL
Xperia™ P (only white led in hardware)
Xperia™ sola
Xperia™ ion
Xperia™ acro HD
Xperia™ go
Xperia™ M
Xperia™ M dual

Note that there's quite a combination of LED types with these phones. Some just have a notification led, some have an LED strip across the bottom and some have both. Also some have only a white illumination bar whereas others have full color support.

There are two settings that control these LEDs to enable or disable them.
In lightflow, settings
    - Illumination bar
    - Main Led Control

If your phone has both types of LED (such as the xperia U) then you can enable both and set them different colors for each in the notifications section of lightflow.

If your phone only has an illumination bar (such as the xperia SP) then you've two options.
Either enable "Illumination bar" and switch off "Main led control" or visa-versa.

If you select Main led control then the led will work when the screen is off only.
If you select illumination bar then the led will work when the screen is on or off.

The Main led control will just light the middle LED of the illumination bar whereas the Illumination bar control will light all 3 LEDs.

If you have both enabled, you may get a mix of both, but the illumination bar controls will generally override the main led color controls.


The led does not work, what can you suggest?
Firstly make sure stamina mode (or extended battery mode) is disabled as this will kill any 3rd party services running in the background (including light flow)
Go into your phone settings->accessibility and switch off and back on lightflow in the list.
Check if there's a setting in your phone settings->display. If there's one regarding the led/light make sure it's on. (don't worry if it's not there)
Switch off your phone with the power button. Then switch it on again.
Go into lightflow -> general settings and make sure direct mode is off.
Then go into notifications -> missed calls.
Set the color to "red"
Set the flash speed to "fast"
Press "test"
Switch off your screen and wait 10 seconds.
Does the LED light up?

If that doesn't work, can you go into your phone settings, apps, choose lightflow and select "clear data" and see if that helps.


Why does the app not work with stamina mode?
This is something I'm looking into. Light flow can be "white listed" by adding it to the exceptions list of apps that are excluded from stamina mode. Note though that if your other apps that are raising notifications are not also in the list, they won't be raising notifications until when the screen is turned by on. Update: it seems that some phones now do work with it, or will put up a message saying that light flow will prevent stamina mode.



I've just upgraded to Ice Cream Sandwich (android 4.0.4) and now the app doesn't work?
I've had a few reports of this on several sony phones upgraded to 4.0.4.

There are quite a few reports in general with the led on sony's support forums so I think it may be a bug in sony's recent rom upgrade.
A quick google search on "sony 4.0.4 notification led" shows up lots of problems.

Hopefully sony will fix it soon.

I'm aware of custom patches for rooted users existing where users have fixed this driver issue sony have created in ICS.

Phone Help HTC

I just get a green light all the time, is my phone supported?
Sadly when HTC started using versions of gingerbread and above (android 2.3.x) on their phones they changed the permissions required to be able to access the LED hardware.

Therefore "root" is now required to be able to control the LEDs.

For more information on rooting, see our faq page at http://www.folioflow.com/ff/page/website/lightflow/pageId/1691

With root access, the app would most likley work in "direct mode".
Note that most HTC phones allow for 3 colors to be chosen (the color limitation is due to the limited hardware in HTC phones). The colors being green and two shades of orange.


Can I get the led to blink?
Select the notification you are interested in, enable the "mixer" option and then for each led you can enable either solid or flashing for it. Note this is only available if you've got root as described above

Phone Help LG G2

I've just upgraded to Lollipop (android 5) and now my back led is strobing
We've had a few reports of this and are looking into the issue. It seems like an LED driver bug in Lollipop but we will try and find a way around the issue.

One way to stop this is to go into your phone settings->display->Notification Light->Rear LED and switch it off

The front LED isn't working
Make sure you go into your phone settings->display->Notification light->Front led and make sure "downloaded apps" is enabled.

The LED's don't work at all.
A few people have been reporting this. So far the only fix seems to be to do a factory reset of the device and choose not to restore existing apps when signing back up. I'm not quite sure why this is, but so far it's fixed the issue for 100% of people who've reported it.

Is it possible to control the back leds?
Yes, but only for root users as LG don't provide any standard access method to it. Once rooted you can enable button-backlight1 and 2 in lightflow->settings. Once enabled you can select them for each notification. There's 1 and 2 as each side of the ring of the led is independent and so can be set up with a different brightness level for each

 I select a color for gmail, but it always shows as green?
There's a workaround for this issue in Light flow from version 3.15.105 upwards

I can't get the app to work, can you help?
If running an android version lower than 4.3:
- Go into your phone settings->accessibility and switch off and back on light flow in the list.

If running android 4.3 or above
- Go into your phone settings->security, notification access and switch off and back on light flow in the list. 

For all versions then
Go into your phone settings->apps(or applications)->select light flow and make sure "show notifications" is checked.
Go into your phone settings->display. Make sure your notification leds are enabled.

Then in the led specific settings switch off all options except "downloaded apps" (on android 4.4.2)

Switch off your phone with the power button.
Then switch it on again. Go into lightflow -> general settings and make sure direct mode is off.
Then go into notifications -> missed calls.
Set the color to "red"
Set the flash speed to "fast"
Press "test" Switch off your screen and wait 10 seconds.

Does the LED light up?

If not, try getting a real missed call as sometimes the test option is less reliable than the real notifications.

If it still doesn't work, try to disable and then re-enable the notification and repeat the test. If that doesn't work, can you go into your phone settings, apps, choose lightflow and select "clear data" and see if that helps.

 
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