diff --git a/src/Message.php b/src/Message.php
index 996419e..69b9b87 100644
--- a/src/Message.php
+++ b/src/Message.php
@@ -157,6 +157,7 @@ public function setTimeToLive($value)
         return $this;
     }
 
+    #[\ReturnTypeWillChange]
     public function jsonSerialize()
     {
         $jsonData = $this->jsonData;
@@ -240,4 +241,4 @@ private function createTarget()
         }
         return null;
     }
-}
\ No newline at end of file
+}