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 @ 10:21
Script: /login.php?sid=9589a9a3e0fd1732fd2b4f3fa7878803
Referer: http://stc-board.de/login.php?sid=9589a9a3e0fd1732fd2b4f3fa7878803