NFC and Flashlight not working

Bought a used iPhone 13 Pro. Now I found out that the NFC (Apple Pay) and the flashlight does not work. I assume that the device has been opened before and something went wrong here, but may be different, because the battery capacity is only 71%. What do you think can be the fault? Do the two functions have something to do with each other, so are they for example on the same chip or something?

Thanks!