SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: SELECT * FROM bb1_info_charaktere WHERE (charakter = 'B��rgermeister' OR (charakter LIKE '%B��rgermeister%' AND charakter LIKE '%;%') OR charakter LIKE 'B��rgermeister%[%') AND synchronsprecher = '---'
mysql error: Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8mb4_unicode_ci,COERCIBLE) for operation '='
mysql error number: 1267
mysql version: 10.5.19-MariaDB-0+deb11u2-log
php version: 5.6.40
Date: 01.06.2023 @ 18:37
Script: /hoerspiele.php?action=search&erw=B%EF%BF%BD%EF%BF%BDrgermeister
Referer: