diff --git a/functions/checkout/index.js b/functions/checkout/index.js
index 56a9e36..d3da681 100644
--- a/functions/checkout/index.js
+++ b/functions/checkout/index.js
@@ -48,7 +48,7 @@ export async function onRequest(ctx) {
 
     const response = Response.json({ 
       error: 400,
-      message: e
+      message: JSON.stringify(e)
     });
 
     response.headers.set("Access-Control-Allow-Origin", "*")