You are not alone, and glad yours was successfully installed ...mine can't detect sim card since the update and yes I can't do a reset because I need to sign in to my account which it won't let me do. Did you find a fix for this ?
hi - hope this can help, its just worked for me - a factory reset so back up everything first. this is a reply from somebody on another thread.
I also initially got stuck at same place, as it was not doing two factor authentication properly, and login needed for reset... ended up powering off... then back on while holding power and volume up. Gets to the bios menu.
Use vol down to get to factory reset, power to select, confirm, and you should be good.