Expected a value of type 'int', but got one of type 'String' json flutter, после hot reload в браузере работает

Пытаюсь вывести в Text декодированный ответ сервера, пробовал запустить и в браузере и на устройстве, на устройстве просто выдает экран ошибки, а в браузере после экрана ошибки всё прогружается и работает как надо.Листинг программы ниже:

   import 'package:http/http.dart' as http;
   import 'package:flutter/material.dart';
   import 'dart:convert';
   String firs_name="";
   List<dynamic> dataList = <String>[""];
   class Message extends StatefulWidget {
   @override
  createState() => new MyWidgetState();
    }




 class MyWidgetState extends State<Message> {
   @override
    Widget build(BuildContext context) {

return new ListView(children: [Container(color: Colors.white60, height: 40,width: 100,
    child:Row(children: [Column(children: [Text(""),Text("Номер телефона")],),Container(
      margin: EdgeInsets.only(left: 10),
      child:
      IconButton(onPressed: (){},icon: const Icon(Icons.check) ,color: Colors.green,),
    ),
      Container(
        margin: EdgeInsets.only(left: 10),
        child:
        IconButton(onPressed: (){},icon: const Icon(Icons.close) ,color: Colors.red,),
      )],
    )
     )

      ],);
  }
   }
             void main() => runApp(MyApp());

int count = 0;
 final List<int> items = <int>[1,2,3,4,5,6];

  class MyApp extends StatefulWidget {
   @override
   State<MyApp> createState() => _MyAppState();
   }

    class _MyAppState extends State<MyApp> {

      Widget build(BuildContext context) {
      void Connect() async {
         var headers = {
    'Content-Type': 'application/json',
  };

  var data = '{""}';


  var url = Uri.parse('******');
  var res = await http.post(url, headers: headers, body: data);
  if (res.statusCode != 200) throw Exception('http.post error: statusCode= 
      ${res.statusCode}');
  print(res.body);
  dataList=jsonDecode(res.body) as List<dynamic>;


  print(dataList);
}
Connect();

return MaterialApp(
  home:
  Scaffold(
    appBar: AppBar(backgroundColor: Colors.orange, title: Text("Подтверждение регистрации",style: TextStyle(fontSize: 15),),
      leading:  Builder(
        builder: (BuildContext context) {
          return IconButton(
            icon: const Icon(Icons.arrow_back),
            onPressed: () {},
          );
        },
      ),
    ),
    body:ListView.builder(
        padding: const EdgeInsets.all(10),
        itemCount: dataList.length,
        itemBuilder: (BuildContext context, int index)
        {
          return Container(
              decoration: BoxDecoration(
                  border: Border.all(
                    color: Colors.white38,
                  ),
                  borderRadius: BorderRadius.all(Radius.circular(20))
              ),
              child: Row(children: [Column(children:
               [Text(dataList[index]['email']),
               // Text(dataList[index]["last_name"]!.toString()),
                //Text(dataList[index]["Patronymic"]!.toString()),
               // Text(dataList[index]["email"]!.toString()),
                ],),Container(
                margin: EdgeInsets.only(left: 20),
                child:
                IconButton(onPressed: (){void Accept_true() async {
                  var headers = {
                    'Content-Type': 'application/json',
                  };

                  var data = '{"email":"${dataList[index]['email']}","accept":"true"}';
                  print(dataList[index]["email"]);
                  var url = Uri.parse('***');
                  var res = await http.post(url, headers: headers, body: data);
                  if (res.statusCode != 200) throw Exception('http.post error: statusCode= ${res.statusCode}');
                }
                Accept_true();},icon: const Icon(Icons.check) ,color: Colors.green,),
              ),
                Container(
                  margin: EdgeInsets.only(left: 20),
                  child:
                  IconButton(onPressed: (){void Accept_false() async {
                    var headers = {
                      'Content-Type': 'application/json',
                    };

                    var data = '{"email":"${dataList[index]['email']}","accept":"false"}';
                    print(dataList[index]["email"]);
                    var url = Uri.parse('***');
                    var res = await http.post(url, headers: headers, body: data);
                    if (res.statusCode != 200) throw Exception('http.post error: statusCode= ${res.statusCode}');
                  }
                  Accept_false();
                  },icon: const Icon(Icons.close) ,color: Colors.red,),
                )],)
          );
        }
    )
    ,),

);

} }