iPhone 8 won't go out of recovery mode whatsoever

Hi, I have an iPhone 8 that I bought off of facebook marketplace and it is stuck in recovery mode. It won’t go out of it no matter what I try, restoring, it wont even go into DFU mode or shut down with the power/volume buttons when in recovery mode. I will restore it, I will have no problems with the restore, then it will just go right back into recovery mode. RecBoot recognized the phone the first time I tried, but just continued spinning trying to exit it out of recovery mode until I got tired of trying it. After that, RecBoot hasn’t recognized it since. The phone might be water damaged, but either way I know a guy who does motherboard repairs so if this is even a board level repair I can get it fixed, it just depends on what it is and thats what I can’t figure out.