SQL-DATABASE ERROR

Database error in WoltLab Burning Board: Link-ID == false, connect failed
mysql error: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)
mysql error number: 2002
Date: 21.05.2024 @ 08:07
Script: /wbb/register.php?sid=81fdfbb5d6e9a4a1bd839ffaa32a9ecf
Referer: http://delftseschaaksite.nl/wbb/register.php?sid=81fdfbb5d6e9a4a1bd839ffaa32a9ecf