Receiving data and display from Firebase [Flutter and Getx]

Question

I'm very new flutter that studying Auth and CRUD with firebase.

I can register, login and post notes data using my real Android phone. And I can see those data are successfully stored at firebase console browser.

But I'm having problem I can not display the post notes data.

Here is my code. Could you teach me what is wrong please?

view.dart:

  import 'package:my_project/app/modules/service_ui/views     
  /receive_tab_bar_view.dart';

  body: TabBarView(
           children: [
            ReceiveView(),
             const DonateTabBarView(),
           ],
         ),
    

receive_tab_bar_view.dart:

 class ReceiveView extends StatefulWidget {
   final DatabaseReference dbRef =
       FirebaseDatabase.instance.ref().child('Receive');

   ReceiveView({super.key});

   @override
   State<ReceiveView> createState() => _ReceiveViewState();
}