diff --git a/html/index.php b/html/index.php
index ac002ab..f068fd2 100644
--- a/html/index.php
+++ b/html/index.php
@@ -36,7 +36,7 @@ function reload(): void {
 }
 
 function newPairing(): array {
-    if ($_REQUEST["csrfToken"] != $_SESSION["csrfToken"]) {
+    if (isset($_SESSION["csrfToken"]) && ($_REQUEST["csrfToken"] != $_SESSION["csrfToken"])) {
         return [$_SESSION["left"], $_SESSION["right"]];
     }