Chosen Solution
My phone was at 2% power and none of my buttons were working. I charged the phone and now only the home button/Siri work. I can not power off the phone or select any of the other buttons like settings or pictures, messages, etc. When i call the phone from another line, it rings but I can not answer it. The phone button is a darker color green than the message button, kind of like it is partially depressed.
I suppose that by buttons, you mean the touch functionality and not the physical buttons, like the Home, Power and Volume buttons. At this point, the first thing to try is a replacement screen, preferably a known-good screen. That will allow you to eliminate an important variable. You can find a replacement screen here and the repair guide here. However, considering the cost of an iPhone 7P screen, you should also consider having this looked at by a reputable repair shop.
