I recently changed my master password through the 1password.com account interface. The change appeared to be accepted but subsequent attempts to login always fail. I am able to change the master password (same new password) on devices, but am unable to login to my 1password.com account from either browsers or devices (using old or new password).
It's possible that I mistyped the new master password into change password form (wrong twice) but I think this is unlikely, and I have tried every likely permutation without success.
If I had to guess, this feels like a bug in the 'change master password' page of the 1password.com site that allows the user to enter a new password (twice) but mangles the string after the match verification step.
I'm going to create a new account and test the same scenario to see if I can reproduce the failure mode.
1Password Version: 6.1.286d
Extension Version: 18.104.22.168
OS Version: Windows 10
Sync Type: Account
Referrer: forum-search:locked out master password change