Blank screen when telephoning on Nexus 6 (Android 5.1) cannot key in options when using call

[AC Question]

In accessability I have activated power key to at least end call but how do use phone when asked to key in information during call with a blank screen

 

[Bhavin Gandhi]

Take your screen-protector out, proximity sensor is being covered by your tempered glass screen protector and is causing issue, next time buy a protector which does not cover the proximity sensor ... seems like a 5.1 issue