21-02-2024 09:02 PM
22-02-2024 01:42 PM
Hello there, @Cristian9806. That's strange that your S21 Ultra is restarting at random and I appreciate that you'll be keen to get to the bottom of this.
While I understand that you've already performed a Factory reset, I'd recommend looking at some of the suggestions in the thread below (albeit about a different phone), as they are likely to help you find and fix the cause of this:
https://eu.community.samsung.com/t5/galaxy-a-series/phone-auto-restarting/m-p/9041401