diff --git a/src/Session.php b/src/Session.php
index 6e14c02..77f0c50 100644
--- a/src/Session.php
+++ b/src/Session.php
@@ -187,6 +187,7 @@ public function setCasToken($token): void
      */
     public function setContents(array $contents): void
     {
+        $this->modified = true;
         $this->contents = $contents;
     }