Flutter:PlatformException (PlatformException(channel-error, Unable to establish connection on channel., null, null))

I have a problem with my flutter app. When I run and use the login feature, it display: PlatformException (PlatformException(channel-error, Unable to establish connection on channel., null, null)). The flow: Sign in Button -> login_controller -> AuthenticationRepository.

Click here for the error picture

/// Sign in button
              SizedBox(
                width: double.infinity,
                child: ElevatedButton(
                  onPressed: () => controller.emailAndPasswordSignIn(),
                  child: const Text(TTexts.signIn),
                ),
              ),

It will use the logic here, and the problem is at the AuthenticationRepository class as shown in the picture (click on the hyperlink). I also have some custom class but I don’t think it will be helpful here. The comment inside the code I think it will be enough. I also have try the flutter clean and flutter pub get but still not working. All the package is up-to-date.

  /// -- Email and Password SignIn
  Future<void> emailAndPasswordSignIn() async {
    try {
      // Start Loading
      TFullScreenLoader.openLoadingDialog(
          'Logging you in...', TImages.docerAnimation);

      // Check Internet Connectivity
      final isConnected = await NetworkManager.instance.isConnected();
      if (!isConnected) {
        TFullScreenLoader.stopLoading();
        return;
      }

      // Form Validation
      if (!loginFormKey.currentState!.validate()) {
        TFullScreenLoader.stopLoading();
        return;
      }

      // Save Data if Remember Me is Selected
      if (rememberMe.value) {
        localStorage.write('REMEMBER_ME_EMAIL', email.text.trim());
        localStorage.write('REMEMBER_ME_PASSWORD', password.text.trim());
      }

      // Login user using Email & Password Authentication
      final userCredentials = await AuthenticationRepository.instance
          .loginWithEmailAndPassword(email.text.trim(), password.text.trim());

      // Save user record
      await userController.saveUserRecord(userCredentials);

      // Remove Loader
      TFullScreenLoader.stopLoading();

      // Redirect
      AuthenticationRepository.instance.screenRedirect();
    } catch (e) {
      TFullScreenLoader.stopLoading();
      TLoaders.errorSnackBar(title: 'Oh Snap!', message: e.toString());
    }
  }

  class AuthenticationRepository extends GetxController {
  static AuthenticationRepository get instance => Get.find();

  /// Variables
  final deviceStorage = GetStorage();
  final _auth = FirebaseAuth.instance;

  /// Get Authenticated User Data
  User? get authUser => _auth.currentUser;

  /// Called from main.dart on app laucnh
  @override
  void onReady() {
    FlutterNativeSplash.remove();
    screenRedirect();
  }

  /// Function to Show Relevant Screen
  void screenRedirect() async {
    final user = _auth.currentUser;

    if (user != null) {
      if (user.emailVerified) {
        Get.offAll(() => const NavigationMenu());
      } else {
        Get.offAll(() => VerifyEmailScreen(
              email: _auth.currentUser?.email,
            ));
      }
    } else {
      // Local Storage
      deviceStorage.writeIfNull('isFirstTime', true);

      // Check if it's the first time launching the app
      deviceStorage.read('isFirstTime') != true
          ? Get.offAll(() => const LoginScreen())
          : Get.offAll(const OnBoardingScreen());
    }
  }

  /* ---------- Email & Password sign-in -----------------*/

  /// [EmailAuthenctication] - SignIn
  Future<UserCredential> loginWithEmailAndPassword(
      String email, String password) async {
    try {
      return await _auth.signInWithEmailAndPassword(
          email: email, password: password); // this where the exception error happen
    } on FirebaseAuthException catch (e) {
      throw TFirebaseAuthException(e.code).message;
    } on FirebaseException catch (e) {
      throw TFirebaseException(e.code).message;
    } on FormatException catch (_) {
      throw const TFormatException();
    } on PlatformException catch (e) {
      throw TPlatformException(e.code).message;
    } catch (e) {
      throw 'Something went wrong. Please try again';
    }
  }
} 

This is my first time doing a complex flutter project and quite newbie on backend/logic programming. Any help/discussion is welcome