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: 10.05.2024 @ 00:47
Script: /memberslist.php?letter=&sortby=userposts&order=ASC&sid=3837b227310f7ff856872b85e9b3bcc2
Referer: http://stc-board.de/memberslist.php?letter=&sortby=userposts&order=ASC&sid=3837b227310f7ff856872b85e9b3bcc2