SQL-DATABASE ERROR

Database error in WoltLab Burning Board (): Link-ID == false, connect failed
mysql error:
mysql error number:
mysql version: unknown
php version: 7.0.33-0ubuntu0.16.04.16
Date: 30.04.2024 @ 23:46
Script: /board/usercp.php?action=buddy&add=14&sid=3f56e5e94a12ad45b6bb6675d599be5b
Referer: