invalidargumentexception

Field: find_new Gives error when I saved any forum. But error is hidden, only saving to log file. XenForo: 2.0.12 Stack trace: #0 src/XF/Mvc/Entity/Entity.php(100): XF\Mvc\Entity\Entity->get('Bu forumdaki ko...') #1 internal_data/code_cache/templates/l2/s0/admin/forum_edit.php(321)...