Unhandled Exception: Bad state: Cannot add event after closing about ion-sdk-flutter HOT 2 OPEN

Uncaught Bad state: Cannot add event after closing
    at Object.wrapException (https://<serverurl>/main.dart.js:13721:17)
    at _AsyncStreamController.add$1 (https://<serverurl>/main.dart.js:62034:17)
    at https://<serverurl>/main.dart.js:120075:52
    at _wrapJsFunctionForAsync_closure.$protected (https://<serverurl>/main.dart.js:23103:15)
    at _wrapJsFunctionForAsync_closure.call$2 (https://<serverurl>/main.dart.js:60915:12)
    at Object._asyncStartSync (https://<serverurl>/main.dart.js:23067:20)
    at WebSocketTransportStream__runRequest_closure0.call$1 (https://<serverurl>/main.dart.js:120080:16)
    at _RootZone.runUnaryGuarded$1$2 (https://<serverurl>/main.dart.js:63018:13)
    at _ControllerSubscription._sendData$1 (https://<serverurl>/main.dart.js:62385:19)
    at _ControllerSubscription._async$_add$1 (https://<serverurl>/main.dart.js:62334:14)

> flutter doctor -v
[✓] Flutter (Channel stable, 2.5.2, on macOS 11.6 20G165 darwin-arm, locale en-IN)
    • Flutter version 2.5.2 at /Users/manishraje/development/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 3595343e20 (3 months ago), 2021-09-30 12:58:18 -0700
    • Engine revision 6ac856380f
    • Dart version 2.14.3

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
    • Android SDK at /Users/manishraje/Library/Android/sdk
    ✗ cmdline-tools component is missing
      Run `path/to/sdkmanager --install "cmdline-tools;latest"`
      See https://developer.android.com/studio/command-line for more details.
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for more details.

[✓] Xcode - develop for iOS and macOS
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 13.1, Build version 13A1030d
    • CocoaPods version 1.10.1

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2020.3)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 11.0.10+0-b96-7281165)

[✓] VS Code (version 1.63.2)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.29.0

[✓] Connected device (2 available)
    • macOS (desktop) • macos  • darwin-arm64   • macOS 11.6 20G165 darwin-arm
    • Chrome (web)    • chrome • web-javascript • Google Chrome 96.0.4664.110

! Doctor found issues in 1 category.

      _channel.stream.listen((message) async {
        final listBuffer = <int>[];
        for (var i = 0; i < message.length; i++) {
          listBuffer.add(message[i]);
        }
=>        _incomingProcessor.add(Uint8List.fromList(listBuffer).buffer);
      }, onDone: _onDone(this), onError: _onError);