After restoring a Logto database, 'password authentication failed' for the tenant DB user happens because the password hash is one-way: you can't recover or reverse it from the backup. Fix: create a dummy database user with a new password, take its password hash (Logto uses Argon2i), and use that hash to update the existing tenant user's password. That restores the credentials without knowing the original password.

_Source: gh:logto-io/logto#7099 (Logto)_