How to get the incoming caller's phone number?

I want to get the incoming caller's phone number in my flutter app I found this code that gives me the number in Android but for some reason, it doesn't work with flutter

I got the broadcastreceiver from here Access phone number of incoming calls in flutter

And this is my main

package com.example.docapp;
 
import androidx.annotation.NonNull;
import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.FlutterEngine;
import io.flutter.plugin.common.MethodChannel;
import io.flutter.plugins.GeneratedPluginRegistrant;
 
import android.content.ContextWrapper;
import android.content.Intent;
import android.content.IntentFilter;
import android.util.Log;
 
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.content.Context;
import android.telephony.TelephonyManager;
import android.telephony.PhoneStateListener;
import android.os.Build;
import android.os.Bundle;
 
 
 
public class MainActivity extends FlutterActivity {
    private static final String PhoneNumber = "www.this.com/callerid";
    private Intent forService;
    String  num;
    int state;
 
 
    @Override
    protected void onCreate(Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        Log.d("Oncreate Main","MAIN MAIN MAIN");
    }
 
 
 
 
 
 
 
    @Override
    public void configureFlutterEngine(@NonNull FlutterEngine flutterEngine){
    super.configureFlutterEngine(flutterEngine);
    forService = new Intent(MainActivity.this,MyService.class);
 
 
 
        new MethodChannel(flutterEngine.getDartExecutor().getBinaryMessenger(),PhoneNumber)
            .setMethodCallHandler(
                (call,result)->{
                   if(call.method.equals("getcallerid")){
 
                        if(Build.VERSION.SDK_INT>=Build.VERSION_CODES.O){
 
 
                        startForegroundService(forService);
                        } else{
 
 
                        startService(forService);
                        }
 
                       result.success("this");
                    Log.d("My Activity","Method in Java");
                   }else{
                       result.notImplemented();
                   }   
                }
            );
        }
 
 
} 

I am trying this on my phone with Android 9.