diff --git a/src/Mailjet/php-mailjet-v3-simple.class.php b/src/Mailjet/php-mailjet-v3-simple.class.php
index 6132c3f..92dde74 100644
--- a/src/Mailjet/php-mailjet-v3-simple.class.php
+++ b/src/Mailjet/php-mailjet-v3-simple.class.php
@@ -311,7 +311,7 @@ public function sendRequest($resource = false, $params = array(), $request = "GE
         }
         else
         {
-            $this->_response = json_decode($buffer);
+            $this->_response = json_decode($buffer, false, 512, JSON_BIGINT_AS_STRING);
         }
 
         if ($request == 'POST') {