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: 05.05.2024 @ 17:19
Script: /search.php?action=user&userid=12&sid=db6711785a94fa429263dc894d23a9ae
Referer: http://stc-board.de/search.php?action=user&userid=12&sid=db6711785a94fa429263dc894d23a9ae