Can't get iOS push notification device token i

I referred to this question to get a device token in order to send push notifications to my app. I created my app using create-react-native-app. Here is the code:

import React, { Component } from 'react';
import {
  Platform,
  StyleSheet,
  AppRegistry,
  Text,
  View,
  PushNotificationIOS
} from 'react-native';

type Props = {};

export default class Apptitude extends Component<Props> {
  constructor() {
    console.log('registering evt listerner in launchpad')
    PushNotificationIOS.addEventLister('register', (token) => {
      this.setState({
        deviceToken: token
      })
    });
  }

  render() {
    return (
      <View>
      </View>
    );
  }
}

PushNotificationIOS.addEventListener('registrationError', (registrationError) => {
  console.lo('was error')
  console.log(reason.message)
  console.log(reason.code)
  console.log(reason.details)
})
// yes I'm aware I've added an event listener in the constructor also. Neither of these callbacks fire
PushNotificationIOS.addEventListener('register', (token) => {
  console.log('this is the token', token);
});
console.log('requesting permissions')
PushNotificationIOS.requestPermissions();

The problem is that the register and the registrationError events never fire. I am prompted to approve permissions and next time the app starts I can use checkPermissions() and confirm that permissions are given. But without the device token, it's impossible to send push notifications to the device. What am I doing wrong?

How about the Xcode part?

You should import TCTPushNotification on you AppDelegate file

#import <React/RCTPushNotificationManager.h>

and implement the follow code to enable the notification and register in your app

    // Required to register for notifications
 - (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings
 {
  [RCTPushNotificationManager didRegisterUserNotificationSettings:notificationSettings];
 }
 // Required for the register event.
 - (void)application:(UIApplication *)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
 {
  [RCTPushNotificationManager didRegisterForRemoteNotificationsWithDeviceToken:deviceToken];
 }
 // Required for the notification event. You must call the completion handler after handling the remote notification.
 - (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo
                                                        fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler
 {
   [RCTPushNotificationManager didReceiveRemoteNotification:userInfo fetchCompletionHandler:completionHandler];
 }
 // Required for the registrationError event.
 - (void)application:(UIApplication *)application didFailToRegisterForRemoteNotificationsWithError:(NSError *)error
 {
  [RCTPushNotificationManager didFailToRegisterForRemoteNotificationsWithError:error];
 }
 // Required for the localNotification event.
 - (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification
 {
  [RCTPushNotificationManager didReceiveLocalNotification:notification];
 }

For more information use the official docs

https://facebook.github.io/react-native/docs/pushnotificationios.html