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: 5.6.40-70+0~20240421.84+debian12~1.gbp0c0ec4
Date: 21.09.2024 @ 01:23
Script: /memberslist.php?letter=&sid=d75490fd3b1fedf529360f4df0e4dc09&sortby=username&order=ASC
Referer: http://stc-board.de/memberslist.php?letter=&sid=d75490fd3b1fedf529360f4df0e4dc09&sortby=username&order=ASC