SW 6.5 abgestürzt

Beim Versuch, sich im Backend (SW 6.5) mit dem Shopware Store zu verbinden:

[Semantical Error] The annotation "@Shopware\Core\Framework\Routing\Annotation\RouteScope" in class SwagExtensionStore\Controller\DataController was never imported. Did you maybe forget to add a "use" statement for this annotation? in /.../custom/plugins/SwagExtensionStore/src/Controller/DataController.php (which is being imported from "/.../custom/plugins/SwagExtensionStore/src/Resources/config/routes.yaml"). Make sure there is a loader supporting the "annotation" type.

Shop ist nun gar nicht mehr erreichbar. Wie kann ich das Problem lösen?