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 @ 00:51
Script: /profile.php?userid=239&sid=6aa0a07b4c6633354d6b4e1c1ac00bb7
Referer: http://stc-board.de/profile.php?userid=239&sid=6aa0a07b4c6633354d6b4e1c1ac00bb7