UnexpectedValueException: Class user (from folder 68d73e06f21b737bad6f39e7984b60aa) does not implement the FolderType interface!

[06-Feb-2025 13:31:03 Europe/Berlin] UnexpectedValueException: Class user (from folder 68d73e06f21b737bad6f39e7984b60aa) does not implement the FolderType interface! in /srv/www/studip/studip-current/lib/models/Folder.php:427 Stack trace: #0 /srv/www/studip/studip-current/public/plugins_packages/data-quest/Serienbriefe/controllers/write.php(81): Folder->getTypedFolder() #1 /srv/www/studip/studip-current/vendor/trails/trails.php(558): WriteController->overview_action() #2 /srv/www/studip/studip-current/app/controllers/studip_controller.php(123): Trails_Controller->perform() #3 /srv/www/studip/studip-current/vendor/trails/trails.php(154): StudipController->perform() #4 /srv/www/studip/studip-current/vendor/trails/trails.php(121): Trails_Dispatcher->map_uri_to_response() #5 /srv/www/studip/studip-current/lib/plugins/core/StudIPPlugin.class.php(205): Trails_Dispatcher->dispatch() #6 /srv/www/studip/studip-current/public/plugins_packages/data-quest/Serienbriefe/Serienbriefe.class.php(79): StudIPPlugin->perform() #7 /srv/www/studip/studip-current/public/plugins.php(61): Serienbriefe->perform()