Please refer to the troubleshooting steps in the following Help Center article:
As noted at the end of the article, if none of the suggestions work, please contact support and provide the required information (as explained in the article). They will usually be able to resolve the problem fairly quickly.
Did you try the other troubleshooting suggestions from the article, and if so, what were the results?
Did your help requests to support include all of the required information as specified in the article (the IP address you were using, and whether you were using a VPN, proxy server, or Tor; the Bitwarden client you were using; the UTC timestamp when the error occurred; and the numerical code in the error message)?
I have the same issue with my master password which is 11 characters, although I have been using face ID login for a long while. Face ID stopped working today, and I cannot use the master password I had written down. I found out the minimum length is 12 characters. How long has 12 characters been the minimum length for Bitwarden master password?