Black screen, after making a call

[TeacherGirl1]

This problem used to happen about once a month or so - very annoying.  However, since I did the update this morning, it happens every time.  I can't retrieve messages because I can't access the number pad of the touch screen.   I've tried the ear proximity sensor, and it is always on, even when removed from case.  The phone has not been dropped etc, and has had sustained no damage.  Please help / advise. 

[Uliwooly]

@TeacherGirl

Does your phone has a protective case, glass and/or film? 

settings > about phone > diagnostics > test > test the proximity sensor 

[TeacherGirl1]

No, I have removed the case, and still have the problem.  Nothing else is on the phone at all

[Niconico1]

I have the same problem. When I make a phone call there is no way I can give up in call, so I have to listen to the robots, and I cn use the phone only when the call is over. The screen is black and does not respond to any other action. That's happend to all the calls including wat's up and messenger. I did the test and the proximity sensor passed.

[_alexdon_]

@Niconico1@TeacherGirl

Clean up the sensor, it is very sensitive and any grease can make it malfunction.

[Niconico1]

I'll do that! Thank you!

[Niconico1]

@alexdon It's working! Thank you! One more question, if you can answer, please! If I saved my pictures in google pictures, can I delete them from the phone memory? I am afraid not to lose them, but still the memory's phone it's almost full...:(

[_alexdon_]

@Niconico1 Not sure, I think they are synced and deleting from one place might remove them for good. Try to back them up to a computer or maybe buy a microSD.

I am glad it worked.

[Niconico1]

@alexdon Thanks for all your advices! Was very helpful!

[TeacherGirl1]

Is the sensor on the screen?  If not, where is it?