diff --git a/php/AuthSCHClient.class.php b/php/AuthSCHClient.class.php
index d20a1281b80866e72195c816c75889e5d701c57e..f2636f9b482996383f8e52a6817c547d72b598e5 100644
--- a/php/AuthSCHClient.class.php
+++ b/php/AuthSCHClient.class.php
@@ -30,8 +30,10 @@ class AuthSCHClient {
             } else {
                 // load tokendata from session
                 $this->tokens = unserialize($_SESSION['tokens']);
-                if($this->tokens->lastUpdate + 3600 < time())
+                if($this->tokens->lastUpdate + 3600 < time()) {
                     $this->reauthenticate();
+                    $_SESSION['tokens'] = serialize($this->tokens);
+                }
             }
         } else {
             $this->tokens = $tokens;