Why have my HTC One back, home and apps buttons stopped working?

[AC Question]

HTC One phone. Back, home and apps buttons not working

The buttons on the bottom of the phone don't respond to touch.

 

[vinnie_boombhats]

Re: HTC One phone. Back, home and apps buttons not working

Is this an ongoing issue or did this problem suddenly develop?

 

[jimmy68]

Re: HTC One phone. Back, home and apps buttons not working

suddenly developed, have tried turning phone off and on, also tried the personalise touch settings option in settings