Getting Error in iOS device

My app run perfectly on android device but when I run app on IOS device I got below error and my app closed after creashing:
This is the exception I am getting when running app on iOS device:

```
Exception: Unable to terminate com.nestohubbroker.nestoHubBroker on F3B27743-357C-423B-B351-40097BCC3246:
ProcessException: Process exited abnormally:

Command: /usr/bin/arch -arm64e xcrun simctl terminate F3B27743-357C-423B-B351-40097BCC3246 com.nestohubbroker.nestoHubBroker
the Dart compiler exited unexpectedly.
```

Here is my main.dart file

```
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'package:flutter_downloader/flutter_downloader.dart';

import 'environment.dart';
import 'nesto_hub_app.dart';
import 'utils/shared_pref.dart';

void main() async {
/// initializing the framework
WidgetsFlutterBinding.ensureInitialized();

/// setting up the orientation of the app to portrait only
await SystemChrome.setPreferredOrientations([DeviceOrientation.portraitUp]);

/// initializing the environment file
await dotenv.load(fileName: Environment.fileName);

/// initializing flutter downloader package
await FlutterDownloader.initialize();

/// initializing the shared preference
await SharedPref().initSharedPreferences();
runApp(const NestoHubApp());
}
```
Here I have initialize the flutter_downloader package