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: 05.05.2024 @ 01:28
Script: /profile.php?userid=1&sid=d5ca5ff83bf4e5f980492e5f9e917c0e
Referer: http://stc-board.de/profile.php?userid=1&sid=d5ca5ff83bf4e5f980492e5f9e917c0e