Notification not receiving in iOS for react native project

I have a react native project. I am able to receive the FCM token successfully but when trying to send a notification, the app doesn't receive the notification.
The steps I followed are as below:

1. Created a project in Firebase Console.
2. Added the Firebase .plist in the projectName through Xcode.
3. ran npm install --save react-native-firebase
4. Added in podfile: pod ‘Firebase/Core’
5. ran pod install
6. Update AppDelegate.m with #import <Firebase.h> and [FIRApp configure];
7. Added the APNS in the Firebase Dashboard for iOS App Cloud Messaging.
8. Updated the capabilities with Push Notification and Background Modes > Remote notification
9. In info.plist FIRAnalyticsDebugEnabled, FirebaseAppDelegateProxyEnabled, FirebaseScreenReportingEnabled is set to No

using const fcmToken = await firebase.messaging().getToken(); I am able to get token.

Below is the code for the notification listener.

async createNotificationListeners() {    /*     * Triggered when a particular notification has been received in foreground     * */    this.notificationListener = firebase.notifications().onNotification((notification) => {        const {            title,            body        } = notification;        this.custom_data = notification.data;        const localNotification = new firebase.notifications.Notification({                show_in_foreground: true,            })            .setSound('default')            .setNotificationId(notification.notificationId)            .setTitle(notification.title)            .setBody(notification.body)        firebase.notifications()            .displayNotification(localNotification)            .catch(err => Alert.alert(err));    });    /*     * If your app is in foreground and background, you can listen for when a notification is clicked / tapped / opened as follows:     * */    this.notificationOpenedListener = firebase.notifications().onNotificationOpened((notificationOpen) => {        if ("title" in notificationOpen.notification.data) {            const {                title,                body,                secret_key,                user_id,                realm_id,                user_os,                user_location            } = notificationOpen.notification.data;            this.props.navigation.navigate('Verify', {                title: title,                body: body,                secret_key: secret_key,                user_id: user_id,                realm_id: realm_id,                user_os: user_os,                user_location: user_location            });        } else {            const {                title,                body,                secret_key,                user_id,                realm_id,                user_os,                user_location            } = this.custom_data;            this.props.navigation.navigate('Verify', {                title: title,                body: body,                secret_key: secret_key,                user_id: user_id,                realm_id: realm_id,                user_os: user_os,                user_location: user_location            });        }    });    /*     * If your app is closed, you can check if it was opened by a notification being clicked / tapped / opened as follows:     * */    const notificationOpen = await firebase.notifications().getInitialNotification();    if (notificationOpen) {        const {            title,            body,            secret_key,            user_id,            realm_id,            user_os,            user_location        } = notificationOpen.notification.data;        this.props.navigation.navigate('FCM', {            title: title,            body: body,            secret_key: secret_key,            user_id: user_id,            realm_id: realm_id,            user_os: user_os,            user_location: user_location        });    }    /*     * Triggered for data only payload in foreground     * */    this.messageListener = firebase.messaging().onMessage((message) => {        console.log("JSON.stringify:", JSON.stringify(message));    });}

Please do let me know if more details required.

EDIT

I have updated the code. Now I am able to get firebase.messaging().onMessage() code working and receive a trigger in the foreground. Still unable to get the notification when the app is in the background. Below is the change which I have made.

const fcmToken = await firebase.messaging().getToken();firebase.messaging().ios.registerForRemoteNotifications().then((flag)=>{        console.log("registered", flag);      }).catch((err)=>{        console.log("message", err);      });

AppDelegate.m

#import "AppDelegate.h"#import <React/RCTBridge.h>#import <React/RCTBundleURLProvider.h>#import <React/RCTRootView.h>#import <Firebase.h>#import "RNFirebaseNotifications.h"#import "RNFirebaseMessaging.h"@implementation AppDelegate- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{  [FIRApp configure];  [[UNUserNotificationCenter currentNotificationCenter] setDelegate:self];  [RNFirebaseNotifications configure];  //[FIRApp configure];  [Fabric with:@[[Crashlytics class]]];  RCTBridge *bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:launchOptions];  RCTRootView *rootView = [[RCTRootView alloc] initWithBridge:bridge                                                   moduleName:@"CymmAuth"                                            initialProperties:nil];  rootView.backgroundColor = [[UIColor alloc] initWithRed:1.0f green:1.0f blue:1.0f alpha:1];  self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];  UIViewController *rootViewController = [UIViewController new];  rootViewController.view = rootView;  self.window.rootViewController = rootViewController;  [self.window makeKeyAndVisible];  return YES;}- (NSURL *)sourceURLForBridge:(RCTBridge *)bridge{#if DEBUG  return [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index" fallbackResource:nil];#else  return [[NSBundle mainBundle] URLForResource:@"main" withExtension:@"jsbundle"];#endif}- (void)application:(UIApplication *)application didReceiveRemoteNotification:(nonnull NSDictionary *)userInfofetchCompletionHandler:(nonnull void (^)(UIBackgroundFetchResult))completionHandler{  [[RNFirebaseNotifications instance] didReceiveRemoteNotification:userInfo fetchCompletionHandler:completionHandler];}- (void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings {  [[RNFirebaseMessaging instance] didRegisterUserNotificationSettings:notificationSettings];}-(void) userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(void (^)(void))completionHandler {  [[RNFirebaseMessaging instance] didReceiveRemoteNotification:response.notification.request.content.userInfo];  completionHandler();}@end

Do let me know if I am missing anything. firebase.notifications().onNotification() doesn't get triggered