IOS Beta 18

Was forced to install the beta 18 and after i did my phone started randomly shutting off on its own after about 10 minutes. my phone is absolutely unusable.

It's a beta. Who forced you to install it? Just uninstall it. Plug it into a computer and put it in DFU mode. You can search the internet for instructions. I hope you have a backup from iOS 17.x.

IOS Beta 18
 
 
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