Did you try rebooting into the previous kernel?
Did you try more reboots, warm or cold, all producing the same obstacle?
Upgraded how, online (Zypper or Yast), or offline (booting installation media)?
How you trying to login? If the GUI login manager (GDM, SDDM, LightDM, etc.), can you reach a vtty (e.g. Ctrl-Alt-F2]), but encounter the same obstacle?
There is an openSUSE page dedicated to
lost password recovery.