iFixit sent me a new screen and that seems to have fixed my fingerprint reader issue. factory reset is NOT required here is the repair procedure i followed to be able to re-use my fingerprint reader (you'll need to do this whenever you swap out a fingerprint reader): (1) swap screens per ifixit docs (2) power on phone to make sure it was successful (3) boot phone into fastboot mode (4) go to google's repair tool (https://pixelrepair.withgoogle.com/udfps) and run it. (5) once the tool finishes, it reboots your phone. (6) after initial reboot, reboot again. (7) you should be able to enroll/scan fingerprints as normal