diff --git a/src/modules/validateWebhook.ts b/src/modules/validateWebhook.ts
index f261c04..ad461b9 100644
--- a/src/modules/validateWebhook.ts
+++ b/src/modules/validateWebhook.ts
@@ -26,7 +26,7 @@ export const validateWebhook = (
   }
   const signature = request.headers["x-signature-ed25519"];
   const timestamp = request.headers["x-signature-timestamp"];
-  const { rawBody } = request;
+  const rawBody = request.rawBody ?? request.body;
   if (
     signature === undefined
     || timestamp === undefined