One week before I encountered the problem, I excitedly installed the beta version of iOS 18 to my iPhone XR. Little did I know that that was the beginning of a nightmare for me. A week or so after the installment, my iPhone's screen suddenly went black and in a few seconds into a process that I found other people have described as a boot loop. This means that my iPhone will attempt to start by getting into the logo screen but then either will it start just for a few seconds before it turns off again or will it just go off. and then the process is repeated again and again. I found that this seems to be a common problem for many people out there who also installed the beta version of this software. I also tried to get help in an Apple Store but they just said that my phone was dead and there was nothing they could do. This is just outrageous! Can't believe that a company as rich as Apple will just release software with this kind of deleterious bugs out there and won't try to help their clients after such a huge mess the cause. Will never buy an iPhone again. You should really try to do better.