diff --git a/classes/ColdTrick/TagTools/Notifications/CreateNotificationRelationshipEventHandler.php b/classes/ColdTrick/TagTools/Notifications/CreateNotificationRelationshipEventHandler.php
index f9d67d2..70e9020 100644
--- a/classes/ColdTrick/TagTools/Notifications/CreateNotificationRelationshipEventHandler.php
+++ b/classes/ColdTrick/TagTools/Notifications/CreateNotificationRelationshipEventHandler.php
@@ -147,9 +147,13 @@ public function getUnsentTagsForEntity(): array {
 			return $this->unsent_tags;
 		}
 		
+		$this->unsent_tags = [];
+		
 		$entity = $this->getNotificationEntity();
+		if ($entity instanceof \ElggEntity) {
+			$this->unsent_tags = tag_tools_get_unsent_notification_tags($entity);
+		}
 		
-		$this->unsent_tags = tag_tools_get_unsent_notification_tags($entity);
 		return $this->unsent_tags;
 	}