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: 09.05.2024 @ 08:22
Script: /index.php?hidecat=2&sid=661ceb5a66cf5fa7b91576c2e2f0d342
Referer: http://stc-board.de/index.php?hidecat=2&sid=661ceb5a66cf5fa7b91576c2e2f0d342