SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: SELECT * FROM bb1_info_hoerspiele WHERE threadid = LIMIT 1
mysql error: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'LIMIT 1' at line 1
mysql error number: 1064
mysql version: 10.1.48-MariaDB-0+deb9u2
php version: 5.6.40
Date: 18.09.2021 @ 09:19
Script: /thread.php?postid=&sid=574fbcc25daa8f7a97bb7a17cada32f9
Referer: