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: 03.05.2024 @ 07:02
Script: /index.php?sid=4ce1df9e19c34d49e0af5e56ef38291f
Referer: http://stc-board.de/index.php?sid=4ce1df9e19c34d49e0af5e56ef38291f