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: 06.05.2024 @ 12:55
Script: /calendar.php?sid=f6c5f2bd4b6085d612b435d14f196ee3
Referer: http://stc-board.de/calendar.php?sid=f6c5f2bd4b6085d612b435d14f196ee3