diff --git a/src/EventSubscriber/SettingsSaveEventSubscriber.php b/src/EventSubscriber/SettingsSaveEventSubscriber.php
index c5acd6d..6a29145 100644
--- a/src/EventSubscriber/SettingsSaveEventSubscriber.php
+++ b/src/EventSubscriber/SettingsSaveEventSubscriber.php
@@ -35,6 +35,11 @@ class SettingsSaveEventSubscriber implements EventSubscriberInterface {
     if ($event->getConfig()->getName() == 'content_lock.settings') {
 
       foreach (array_filter($event->getConfig()->get('types')) as $type => $value) {
+        // Skip if the entity type does not exist.
+        if (!$this->entityTypeManager->getDefinition($type, FALSE)) {
+          continue;
+        }
+
         // Create an action config for all activated entity types.
         $action = $this->entityTypeManager->getStorage('action')->loadByProperties([
           'plugin' => 'entity:break_lock:' . $type,