Future Builder having data on Second hot reload

Question

i have a future builder that get data from firestore. the data is coming but futurebuilder is not awaiting it the first time. when i hot reload it works

firestore code below

Future<List<ScheduleWithCourse>> getcourse() async {
    List<ScheduleWithCourse> s = new List<ScheduleWithCourse>();
    await appliedCoursesCollication
        .where("uid", isEqualTo: uid)
        .getDocuments()
        .then((doc) {
      doc.documents.forEach((f) async {
       await scheduleCollection
            .where("courseId", isEqualTo: f.data['courseId'])
            .getDocuments()
            .then((doc) {
          doc.documents.forEach((d) {
            s.add(ScheduleWithCourse(
                tag: d.data['tag'],
                course: Map.from(d.data['course']),
                time: d.data['time'],
                dep: d.data['dep'],
                dayOfWeek: d.data['dayOfWeek']));
          });
        });
      });
    });

    return s;
  }

Future builder code

Future<List<ScheduleWithCourse>> _course;

  @override
  void initState() {
    super.initState();
    _course = DatabaseService().getcourse();
  }

FutureBuilder<List<ScheduleWithCourse>>(
                                future: _course,
                                builder: (context, snapshot) {
                                  if (!snapshot.hasData) {
                                    return Loading();
                                  }  else {
                                    print(snapshot.data.length);
                                    return CarouselSlider(
                                      autoPlay: false,
                                      enlargeCenterPage: true,
                                      aspectRatio: 2.0,
                                      reverse: false,
                                      height:
                                          MediaQuery.of(context).size.height /
                                              4,
                                      viewportFraction: 0.9,
                                      onPageChanged: (index) {},
                                      enableInfiniteScroll: false,
                                      items: snapshot.data.map((f) {
                                        return Builder(
                                          builder: (BuildContext context) {
                                            return Sschedule(schedule: f);
                                          },
                                        );
                                      }).toList(),
                                    );
                                  }
                                }),

when i remove the initstate it only displays the data for a second and then it disappears