Deprecated API cloud messeging and main file give me an error OneSingel class is not initializing

[Muhammad-Ismail-Qazi]

import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:get/get_navigation/src/root/get_material_app.dart';
import 'app/routes/app_pages.dart';
import 'firebase_options.dart';
import 'package:onesignal_flutter/onesignal_flutter.dart';

const ONESIGNAL_APP_ID = "My App ID";

void main() async {
WidgetsFlutterBinding.ensureInitialized();

// Firebase initialization (assuming correct configuration)
await Firebase.initializeApp(
options: DefaultFirebaseOptions.currentPlatform,
);

OneSignal.Debug.setLogLevel(OSLogLevel.verbose);
OneSignal.initialize(ONESIGNAL_APP_ID);
OneSignal.Notifications.requestPermission(true);

runApp(
GetMaterialApp(
title: "Application",
initialRoute: AppPages.INITIAL,
getPages: AppPages.routes,
),
);
}