If you lost access to the Bugzilla account or other account due to not being able to enter TOTP code or using a recovery code for 2FA then normally your only option is to create a new account with a different email address. That is why it is important to have a backup of the recovery codes in a safe place.

You can also keep a backup of the QR code used to initialize the authenticator app.

In the event that the passwords information is lost, you should record all information in a separate text file somewhere else on your hard drive, or written down. You can easily copy and paste if you need to do so. If you are concerned about someone else looking at that file, you can compress it using a password.

I am facing the same problem. I can recover the account, but I can't find my earlier passwords. due to en error in update, my copies of recovery key became corrupted.