diff --git a/lib/pages/section/bloc/section_bloc.dart b/lib/pages/section/bloc/section_bloc.dart
index 698bf57..0c1d94c 100644
--- a/lib/pages/section/bloc/section_bloc.dart
+++ b/lib/pages/section/bloc/section_bloc.dart
@@ -67,9 +67,12 @@ class SectionBloc extends Bloc<SectionEvent, SectionState> {
       RequestDataEvent event, Emitter<SectionState> emitter) async {
     try {
       await loading(() async {
-        _courseSectionDatasMap[event.courseUnitId] =
-            await LessonDao.courseSection(courseUnitId: event.courseUnitId);
-        emitter(LessonDataLoadState());
+        List<CourseSectionEntity>? courseSectionEntities = await LessonDao.courseSection(courseUnitId: event.courseUnitId);
+        if (courseSectionEntities != null) {
+          _courseSectionDatasMap[event.courseUnitId] =
+          await LessonDao.courseSection(courseUnitId: event.courseUnitId);
+          emitter(LessonDataLoadState());
+        }
       });
     } catch (e) {
       if (e is ApiException) {