I had this problem after my boyfriend replaced the battery on my Pixel 5. Battery replacement was successful but the touch screen wouldn’t respond. We took it apart again and saw that three of the connector pins on the motherboard were lodged slightly askew. We repositioned them and when we tried to put the screen down it dislocated the pins on the motherboard connector again. After several tries he was able to line the pins up again, get the screen closed without dislodging them, and now the phone works. FYI, these connector pins are minuscule and if you have to do this, get a magnifying glass. It will make it so much easier.