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: 11.05.2024 @ 22:08
Script: /thread.php?threadid=380&threadview=0&hilight=&hilightuser=0&page=11&sid=3a8d976cd04d3b1be2cbb3d41b8e7d4c
Referer: http://stc-board.de/thread.php?threadid=380&threadview=0&hilight=&hilightuser=0&page=11&sid=3a8d976cd04d3b1be2cbb3d41b8e7d4c