diff --git a/components/Timetable/Timetable.tsx b/components/Timetable/Timetable.tsx
index 917f393..df9db47 100644
--- a/components/Timetable/Timetable.tsx
+++ b/components/Timetable/Timetable.tsx
@@ -21,7 +21,7 @@ interface TimetableItem {
   section: string | null;
   e: string;
   j: string;
-  schedule: string;
+  schedule: string | null;
   room: string | null;
   comment: string | null;
   maxnum: string | null;