SQL-DATABASE ERROR

Database error in WoltLab Burning Board: Invalid SQL: SELECT threadid FROM bb1510_threads t WHERE visible = 1 AND important < 2 AND closed !=3 AND t.boardid NOT IN (0,Konferenzraum, Sonja) AND t.boardid IN (3) ORDER BY lastposttime DESC LIMIT 5
mysql error: Unknown column 'Konferenzraum' in 'where clause'
mysql error number: 1054
Date: 15.12.2018 @ 15:45
Script: /portal.php
Referer: