SQL-DATABASE ERROR

Database error in WoltLab Burning Board (): Link-ID == false, connect failed
mysql error: Connection refused
mysql error number: 2002
mysql version: unknown
php version: 5.6.40-57+0~20211119.60+debian9~1.gbp8a9bd1
Date: 08.05.2024 @ 22:36
Script: /search.php?action=user&userid=9&sid=a1485edc2aaeb2a3a53e0bb36f78a539
Referer: http://stc-board.de/search.php?action=user&userid=9&sid=a1485edc2aaeb2a3a53e0bb36f78a539