If it's in warranty use that but out of warranty try a factory reset, restore your stuff from backup and hope.
This is not a "soft turn off" the effect is like holding the power button. it will go black. Also its settings app is missing and the action center is gone. its completely random and will do it even if I open the start menu sometimes. it occasionally does it on the sign in screen. I need help soon as this is my school computer.

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