SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.1.3): Invalid SQL: SELECT a.replycount AS replies,a.boardid AS boardparentid,a.threadid AS threadid,a.topic AS threadname FROM bb2_threads AS a,bb2_boards AS b WHERE a.boardid = b.boardid ORDER BY a.replies DESC
mysql error: Unknown column 'a.replies' in 'order clause'
mysql error number: 1054
mysql version: 5.7.25
php version: 5.6.40
Date: 28.04.2024 @ 01:37
Script: /forum/statistik.php?sid=b8b37cee0db92b10b4d77bb79ad2e0be
Referer: