SCRAM needs newer lib. Probably Wayne circumvented the authentication problem using the old method, changing the v10+ SCRAM (Salted Challenge Response Authentication Mechanism) to the less safer MD5 on pg_hba.conf
Notice your authentication must be compatible with the current stored encrypted one, or before trying it again, you must change the encryption method (password_encryption) and change the desire password (psql command \password) to store a new correct one.