I got the same issue on my iphone 7 plus : Touch id works but not home button
There were no sound as well.
This happens after a screen changing.
The correct solution for me was the note on step 28 of the iphone tutorial for front camera changing : [guide|95688]
“When reassembling, verify the tape is in place, or else cover the contacts on the back of the cable with an appropriate tape, such as Kapton tape.”
Hope it can help,
Regards,
Apricc