diff --git a/app/Client/Ccp/Sso/Sso.php b/app/Client/Ccp/Sso/Sso.php
index 2a43626..9f1039c 100644
--- a/app/Client/Ccp/Sso/Sso.php
+++ b/app/Client/Ccp/Sso/Sso.php
@@ -57,7 +57,7 @@ function($body) : array {
      */
     protected function getAccessRequest(array $credentials, array $requestParams = []) : RequestConfig {
         $requestOptions = [
-            'json' => $requestParams,
+            'form_params' => $requestParams,
             'auth' => $credentials
         ];
 
@@ -102,4 +102,4 @@ public function getVerifyAuthorizationCodeEndpointURI() : string {
     protected function getConfig() : ConfigInterface {
         return ($this->config instanceof ConfigInterface) ? $this->config : $this->config = new Config();
     }
-}
\ No newline at end of file
+}