有点奇怪的是，blocListener没有监听我的状态变化，我的状态永远是null，为什么会这样？
一点帮助或见解将不胜感激。
user_cubit.dart

UserCubit() : super(UserInitialState()) {
    emit(UserMainLoadingState());
    _firestore
        .collection("users")
        .doc(_currentUser?.uid) // or whatever your collection name is
        .snapshots()
        .listen((event) {
      event.exists
          ? {
              print("User Exists"),
              emit(state.copyModel(
                  userModel: UserModel.fromjson(event.data()!, event.id))), // Here I am using copyModel , as a additional method
              emit(UserExists(
                  userModel: UserModel.fromjson(event.data()!, event.id)))
            }
          : {print("There is no such user"), emit(UserNotExists())};
    });
  }

user_state.dart

class UserState extends Equatable {
  final UserModel? userModel;
  const UserState({this.userModel});

  UserState copyModel({required UserModel userModel}) {
    return UserState(userModel: userModel);
  }

  @override
  List<Object?> get props => [userModel];
}

class UserExists extends UserState {
  UserExists({required UserModel userModel}) : super(userModel: userModel) {

  }
}

my_widget.dart

body: BlocListener<UserCubit, UserState>(
          listener: (context, state) {
              print("I am inside the listener");
            if (state.userModel != null) {
              print("State is ${state.runtimeType}");

            }
          },
          child: <My widget>

console

I/flutter ( 5029): I am inside the UserExists state and the user is :avatar boy
I/flutter ( 5029):  fullName krrrt
I/flutter ( 5029):  dob 19/1/2022
I/flutter ( 5029):  email rd@xddf.co
I/flutter ( 5029):  phone 12222222255

令人惊讶的是，打印I am inside the listener从未执行。
在listener中，我想初始化一些变量，比如textfield，但是我的状态总是空的，我不知道为什么，尽管我已经更新了状态，并且状态里面有值。
一点帮助将不胜感激
编辑：
User_model.dart

class UserModel {
  final String avatar;
  final String fullName;
  final String phoneNumber;
  final String dob;
  final String email;
  String? id;

  UserModel(
      {required this.avatar,
      required this.dob,
      required this.email,
      required this.fullName,
      required this.phoneNumber});

  factory UserModel.fromjson(Map<String, dynamic> json, String id) {
    return UserModel(
        avatar: json['avatar'],
        dob: json["dob"],
        email: json['email'],
        fullName: json['fullName'],
        phoneNumber: json['phoneNumber']);
  }
  Map<String, dynamic> toJson() {
    return {
      'fullName': fullName,
      'dob': dob,
      'avatar': avatar,
      'email': email,
      'phoneNumber': phoneNumber,
    };
  }

  @override
  String toString() {
    // TODO: implement toString
    return "avatar $avatar \n fullName $fullName \n dob $dob \n email $email\n phone $phoneNumber ";
  }
}