diff --git a/src/middlewares/authInternal.ts b/src/middlewares/authInternal.ts
index 8d29ceb6..d3d9a5b6 100644
--- a/src/middlewares/authInternal.ts
+++ b/src/middlewares/authInternal.ts
@@ -7,7 +7,7 @@ import HttpStatus from "../interfaces/http-status";
 export async function handleInternalAuth(request: express.Request) {
   // รองรับ header หลายรูปแบบ
   const apiKey =
-    request.headers["api-key"] || request.headers["apikey"];
+    request.headers["api-key"] || request.headers["api_key"] || request.headers["apikey"];
 
   if (!apiKey || typeof apiKey !== "string") {
     throw new HttpError(HttpStatus.UNAUTHORIZED, "API Key is required");