What is wrong with my code ?

I am fairly new to Xcode and swift. I am trying to send a notification from firebase to my app . Thanks Again

import Firebase

import FirebaseMessaging

import UserNotifications

import UIKit

@main

class AppDelegate: UIResponder, UIApplicationDelegate, MessagingDelegate, UNUserNotificationCenterDelegate {

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

    Messaging.messaging().delegate = self

    UNUserNotificationCenter.current().delegate = self

    UNUserNotificationCenter.current().requestAuthorization(options:[.alert, .sound, .badge]) {success, _ in guard success else {

                  return

            }

    print("Success in APNS registry")

        }

    application.registerForRemoteNotifications()

        return true

    }

    func messaging(_ messaging: Messaging, didReceiveRegistrationToken fcmToken: String?) {

        messaging.token {token, _ in

            guard let token = token else {

                return

            }

        print("Token: (token)")

        }

    }

}