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: 28.04.2024 @ 10:50
Script: /board.php?boardid=52&page=1&daysprune=1000&sortfield=starter&sortorder=ASC&sid=6d267f61e3c13f6b8b0b6ce206a03032
Referer: http://stc-board.de/board.php?boardid=52&page=1&daysprune=1000&sortfield=starter&sortorder=ASC&sid=6d267f61e3c13f6b8b0b6ce206a03032