Do a hard reset on it.
Heres How:
Firstly, you need to quick-press the Volume Up button. That is, press it for a second or less and release it quickly. Without waiting anymore, quick-press the Volume Down button. Now, press and hold the Side button for at least 10 seconds. Keep pressing the Side button till the screen would vibrate. Let go of it once you see the Apple logo on the screen.
[br]