diff --git a/src/Model/Message/PushNotification.php b/src/Model/Message/PushNotification.php
index b87ab76..216be1d 100644
--- a/src/Model/Message/PushNotification.php
+++ b/src/Model/Message/PushNotification.php
@@ -87,9 +87,16 @@ public function createMessage(array $options = [], array $auth = []): PushMessag
 
     public function jsonSerialize(): array
     {
+        $options = [];
+        foreach ($this->options as $key=>$option) {
+            if($option !== null){
+                $options[$key] = $option;
+            }
+        }
+
         return [
-            'title' => $this->title,
-            'options' => array_diff($this->options, array_filter($this->options, 'is_null')),
+            'title'   => $this->title,
+            'options' => $options
         ];
     }