I have 2 machines, one is on High Sierra and one is running Catalina. I do not have a membership, I use 1Password standalone and "sync" by copying the 1Password.opvault file as required for latest updates from the High Sierra machine to the Catalina machine. This works well for me since I cannot use an external/online sync per company policy.
For one particular site I continually get an error message from the site that the username or password is incorrect when using the Catalina machine and Safari version 13.0.5. I can successfully log in with the stored username and password from the High Sierra machine also running Safari 13.0.5. I can verify that the usernames and passwords are identical.
I can move the .opvault file from the Catalina machine back to the High Sierra machine and it will work so the UN and PW are stored correctly.
I am completely baffled as to why the same .opvault file fails on Catalina but works under High Sierra.
Both machines are running 1Password version 7.4.3
1Password Version: Not Provided
Extension Version: Not Provided
OS Version: Not Provided
Sync Type: Not Provided