diff --git a/src/Plugin/Action/AbstractGenerateDerivativeMediaFile.php b/src/Plugin/Action/AbstractGenerateDerivativeMediaFile.php
index f484fdc3..be9eca80 100644
--- a/src/Plugin/Action/AbstractGenerateDerivativeMediaFile.php
+++ b/src/Plugin/Action/AbstractGenerateDerivativeMediaFile.php
@@ -40,7 +40,7 @@ class AbstractGenerateDerivativeMediaFile extends AbstractGenerateDerivativeBase
   protected function generateData(EntityInterface $entity) {
     $data = parent::generateData($entity);
     if (get_class($entity) != 'Drupal\media\Entity\Media') {
-      return;
+      throw new \RuntimeException("Entity {$entity->getEntityTypeId()} {$entity->id()} is not a media", 500);
     }
     $source_file = $this->mediaSource->getSourceFile($entity);
     if (!$source_file) {