About every 1 in 3 times I try to turn the phone on, the screen remains black, but I know it has "woken up", because it vibrates under my finger to indicate it has unlocked. Additionally, swiping around while the screen is black results in opening main screen apps. I have tried face unlock, fingerprint and voice unlock and these methods all have the same kind if success rate. I've found the only way of turning the screen on is, after unlocking it, is to hold the power button to bring up the force shutdown menu. This issue has gotten progressively worse over a number of weeks. I run an app launcher, may be contributing? The phone is about a year old. Help!
