Sony xperia Z3 Compact: Display goes to sleep after a few seconds

[AC Question]

I charged my phone this morning and found that since then the display goes to sleep after a few seconds.

I need to unlock the screen after I push the power button to wake it up again.

I've checked the Sleep setting and turned it to 5 minutes.

Any ideas on what the problem may be and how to fix it? It's difficult to troubleshoot when I have to keep waking the display up.

 

[B. Diddy]

Welcome to Android Central! Any power saving modes turned on? Also, make sure there aren't any magnets nearby, since they could trigger the smartcover sensor that most phones have.