Headless JS Background task is not running in React-Native

import {AppRegistry} from 'react-native';
import App from './App';
import task from './src/task';
import {name as appName} from './app.json';


//AppRegistry.registerComponent('App',()=>App);
AppRegistry.registerHeadlessTask('SomeTaskName', () =>
task
);

package com.convertwebsitetoapp;
import android.content.Intent;
import android.os.Bundle;
import com.facebook.react.HeadlessJsTaskService;
import com.facebook.react.bridge.Arguments;
import com.facebook.react.jstasks.HeadlessJsTaskConfig;
import javax.annotation.Nullable;

public class MyTaskService extends HeadlessJsTaskService {

  @Override
  protected @Nullable HeadlessJsTaskConfig getTaskConfig(Intent intent) {
    Bundle extras = intent.getExtras();
    if (extras != null) {
      return new HeadlessJsTaskConfig(
          "SomeTaskName",
          Arguments.fromBundle(extras),
          5000, // timeout for the task
          false // optional: defines whether or not  the task is allowed in foreground. Default is false
        );
    }
    return null;
  }
}

task.js
module.exports = async (taskData) => {
    console.log('Demo')
    
  };

I am new in React-Native. Trying to create an app using headless js in react-native When i start MyTask service inside oncreate method then the app is crashing and not opening. And when am registering without component registerheadlessjs task then am getting the error as "registercompoent was not called" Please give me one simple example if anyone has.

Thanks in advance