diff --git a/public/upsell.html b/public/upsell.html
index 25cbe05..2512d3b 100644
--- a/public/upsell.html
+++ b/public/upsell.html
@@ -130,7 +130,8 @@ const webhookPost = webhookUrl + "/submit-data";
       const res = await fetch(webhookUrl, {
         method: "POST",
         headers: {
-          "Content-Type": "application/json"
+          "Content-Type": "application/json",
+          "credentials": "include"
         },
         body: JSON.stringify({ uuid }) // send uuid in request body
       });