diff --git a/packages/hydrooj/src/error.ts b/packages/hydrooj/src/error.ts
index 1802cb1b7..0c50ff3a4 100644
--- a/packages/hydrooj/src/error.ts
+++ b/packages/hydrooj/src/error.ts
@@ -167,6 +167,7 @@ global.Hydro.error = {
     MessageNotFoundError,
     FileTooLargeError,
     CurrentPasswordError,
+    DiscussionLockedError,
 };
 
 /*