diff --git a/src/Exception/OAuthServerException.php b/src/Exception/OAuthServerException.php
index fe615262..14297e75 100644
--- a/src/Exception/OAuthServerException.php
+++ b/src/Exception/OAuthServerException.php
@@ -295,7 +295,7 @@ class OAuthServerException extends \Exception
         // matching the authentication scheme used by the client.
         // @codeCoverageIgnoreStart
         if ($this->errorType === 'invalid_client' && array_key_exists('HTTP_AUTHORIZATION', $_SERVER) !== false) {
-            $authScheme = strpos($_SERVER['HTTP_AUTHORIZATION'], 'Bearer') === 0 ? 'Bearer' : 'Basic';            
+            $authScheme = strpos($_SERVER['HTTP_AUTHORIZATION'], 'Bearer') === 0 ? 'Bearer' : 'Basic'; 
 
             $headers['WWW-Authenticate'] = $authScheme . ' realm="OAuth"';
         }