Screen auto lock on iPhone does not work My 2 week old iPhone 8 won’t lock automatically after the set limit of 30 seconds. My phone remains unlocked until I physically press the lock screen button. 

Even then, if the screen is touched, the display wont turn off itself.  

How can I get my autolock screen function to work?
I had the same problem with my iphone 8 and this morning kept googling answers thinking it was a major problem.  Then I have restarted the phone and it now works.  Should have done this first! lol