Screen Doesn't Turn Off - Ignores Timeout Option

Ok so it might be some user app so first you have to do is turn your display to 15 secs then find the oldest version of 360 security and install it and keep forcestopping each app you can even do it manually in settings/storage/apps/downloaded.......if this doesn't work then check if the developers option is turned on in the settings if it's on turn it off and check......if this doesn't work either then do a factory reset
 
Just created an account to say that my issue on Nexus 7 2012 tablet with Lineage OS 14.1 was resolved by disabling Developer Tools.
 
Unreal! After all this time, just uninstalling AirDroid seems to be working for me (so far). Thanks Armin_sq!!!