Can I get some help with my Lumia 640 back button and lockscreen issues?

[Stevie Kyles]

Lumia 640 "back" button and lockscreen issues

Two issue with my phone (1) if I'm playing a game or viewing picture, the back button no longer appears when I tap the lower screen. The only way to recover is to turn the phone off and back on. Issue (2) once a phone call starts, the screen goes black and does not return until the call is ended by the person on the other end, so I'm screwed if I want to place the call on speaker, end the call, or press "1" for English! Any ideas?

 

[libra89]

Re: Lumia 640 "back" button and lockscreen issues

That's an interesting issue with number 2. Do you have Glance enabled?

 

[jacob103]

Re: Lumia 640 "back" button and lockscreen issues

Sounds like a proximity censor is bad. Had that issue with my 928 back last year. And the first one swipe up from the bottom and see if that brings back up the back button.

 

[Diamond67]

Re: Lumia 640 "back" button and lockscreen issues

And the first one swipe up from the bottom and see if that brings back up the back button.

Yes. Swiping up should bring it back. Swipe up again, and it should be invisible. Swipe up, not tap.

 

[Rose640]

About the capacitive screen buttons just swipe up fro the bottom, not tap, swipe, or if you like you could turn that off following these steps: go to settings -> navigation bar -> and uncheck the first setting, that is auto hide/show option.

About the calling issue, I'm using my device for almost two weeks now and I have to be honest I didn't get that kind of problem, like all the others I'm guessing its up to the proximity sensor. Try performing soft reset by pressing and holding the volume down+power buttons for about 10 secs. Now if this doesn't work try performing a second, hard reset, go to settings -> about -> reset my phone. Note that if you hard reset your phone you'll loose all of your data that hasn't been backed up (no OS or firmware updates will be lost).

Again, if this doesn't work then you'll have to take to the shop and have it fixed/replaces there.