diff --git a/app/auth/callback/route.ts b/app/auth/callback/route.ts
index 3a4573d..40e207f 100644
--- a/app/auth/callback/route.ts
+++ b/app/auth/callback/route.ts
@@ -26,7 +26,7 @@ export async function GET(request: Request) {
       error_description,
     });
 
-    let message = AUTH_ERROR_MESSAGES.DEFAULT;
+    let message: string = AUTH_ERROR_MESSAGES.DEFAULT;
 
     // 에러 종류에 따른 메시지 분기
     if (error === "access_denied") {