diff --git a/src/Routing/Enhancer/RngRouteEnhancer.php b/src/Routing/Enhancer/RngRouteEnhancer.php
index b508eec..153f79e 100644
--- a/src/Routing/Enhancer/RngRouteEnhancer.php
+++ b/src/Routing/Enhancer/RngRouteEnhancer.php
@@ -22,13 +22,13 @@ public function applies(Route $route) {
    * {@inheritdoc}
    */
   public function enhance(array $defaults, Request $request) {
-    $event_entity_type = $defaults['event'];
-
-    if (isset($defaults[$event_entity_type])) {
-      $rng_event = $defaults[$event_entity_type];
-      $defaults['rng_event'] = $rng_event;
+    if(!empty($defaults['event'])){
+      $event_entity_type = $defaults['event'];
+      if (isset($defaults[$event_entity_type])) {
+        $rng_event = $defaults[$event_entity_type];
+        $defaults['rng_event'] = $rng_event;
+      }
     }
-
     return $defaults;
   }