My pc randomly gets stuck into infinite restart loops

This has happened more often with fortnite, where ill be playing and randomly the game would be running at less than 1fps and sound would glitch till pc shuts down, at that point it restarts but fails to reach the lockscreen and does it one more time till it restarts at the diagnostics page. I have tried to use the options on the diagnostics page but those have to worked. The only thing that really has worked is shutting the pc down fully and taking the power cable out of the pc and then restarting. I have not found someone with my issue yet and ive had this going on since september. I have a 3070, ryzen 7 5700X and a 750W power supply (https://www.amazon.co.uk/dp/B0CJRXNXZT). I built this pc last year so I was not expecting it be throttling. If someone has encountered this issue please let me know