diff --git a/Service/AsyncEvent/HttpNotifier.php b/Service/AsyncEvent/HttpNotifier.php
index 8e9c3ad..a27f41a 100644
--- a/Service/AsyncEvent/HttpNotifier.php
+++ b/Service/AsyncEvent/HttpNotifier.php
@@ -48,7 +48,8 @@ public function notify(AsyncEventInterface $asyncEvent, CloudEventImmutable $eve
                 self::HASHING_ALGORITHM,
                 $body,
                 $this->encryptor->decrypt($asyncEvent->getVerificationToken())
-            )
+            ),
+            'content-type' => 'application/json'
         ];
 
         $notifierResult = new NotifierResult();