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: 07.05.2024 @ 00:58
Script: /thread.php?goto=nextnewest&threadid=649&sid=7a97dce3c0f8640f3f4543afc30999de
Referer: http://stc-board.de/thread.php?goto=nextnewest&threadid=649&sid=7a97dce3c0f8640f3f4543afc30999de