SQL-DATABASE ERROR

Database error in WoltLab Burning Board: Invalid SQL: SELECT username FROM bb449_users WHERE userid='28'A=0'
mysql error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'A=0'' at line 1
mysql error number: 1064
Date: 05.08.2020 @ 17:42
Script: /wiw.php
Referer: