If you have next problem: iPhone freeze, does not react on face recognition, or buttons. Screen can be black, when power is plugged on, display shorty shows locked screed.
Try the next:iPhones with face recognition: shortly press the Volume Up, then the Volume Down and then press the Power button, until device restarts (10-20 sec).
iPhones or later: shortly press the Volume Up, then the Volume Down and then press the Side button, until Apple logo shows (10-20 sec).
iPhone 7, 7 Plus and iPod Touch: Press and hold at the same time the Top (or the Side) button and the Volume Down, until shown Apple logo on the screen.
iPhones with the Home button: Press and hold at the same time the Top (or the Side) button and the Home, until shown Apple logo on the screen.
If it still does not react, device battery can be totally empty. Please, let it charging. After one or two minutes should on screen appear battery icon. Also, charger and cable should be checked if it does not work.
