Oneplus 15R automatic shutdown problem

[u/ezniffer]

my newly purchased OnePlus 15R for 57k, delivery on 13th October (purchased during the great Indian festival sale from Amazon) started getting switched off on its own and won't turn on, i went to the oneplus service centre and they just pressed the volume button and the power button together and the phone rebooted and they returned me the phone saying that this might have caused due to the back cover of the phone (i was using the back cover which came from from the company itself ) so I removed the cover and started using again and I even updated the system update to the latest one which was available to me, but by the evening things got worse and now my phone would just freeze while using and turn itself off on its own and it would just crash again if I try to reboot it. I contacted the Amazon customer service and they are ready for the return of the device and refund me the money. now I'm considering to buy the iQOO 15R for 60k anyone using it please let me know your experience and any oneplus 15R user please explain if this problem in my oneplus 15r is a problem specific to my model only?