Hello,
Thank you for posting in the Microsoft community forum.
May I know if you can use PIN unlock to access desktop on your local device? If you can, please try to go to Settings > Accounts > Sign-in options. From there, turn OFF the Additional settings "For improved security, only allow Windows Hello sign-in for Microsoft accounts on this device (Recommended)". After doing so, remove your PIN then restart the device. Try to log in with the changed password. If the login is successful, you can reconfigure the PIN.
I hope this helps. If you have any follow-up questions, please contact us.
Best regards
Jacen