iPhone 8 Plus Boot loop and cannot fix it.

So what happened was I bought this iPhone 8 Plus from ebay and the seller didn't specify that it was on boot loop so when I got it, it was packaged like brand new so i didn't expect anything but the phone to work, so how bout i open it up and turn the phone on it was boot looping and I tried every method and it still didn't work, PLS HELP!!!!