'didRegisterForRemoteNotificationsWithDeviceToken' never called

Code Block 
import UIKit
import UserNotifications
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterDelegate {
    /// The base UIWindow
    var window: UIWindow?
    func application(_ application: UIApplication, didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data) {
        let token = deviceToken.map { String(format: "%02.2hhx", $0) }.joined()
        print("token: \(token)")
    }
    func application(_ application: UIApplication, didFailToRegisterForRemoteNotificationsWithError error: Error) {
        print("Failed to register for remote notifications with error: \(error))")
    }
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        // Override point for customization after application launch.
        UNUserNotificationCenter.current().delegate = self
        UIApplication.shared.registerForRemoteNotifications()
        UNUserNotificationCenter.current().requestAuthorization(
            options: [.alert, .badge, .sound],
            completionHandler: { (granted, error) in
                print("access granted!")
                guard granted else { return }
                DispatchQueue.main.async {
                    UIApplication.shared.registerForRemoteNotifications()
                    print("Registered: \(UIApplication.shared.isRegisteredForRemoteNotifications)")
                }
            })
        return true
    }
    // MARK: UISceneSession Lifecycle
    func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
        // Called when a new scene session is being created.
        // Use this method to select a configuration to create the new scene with.
        return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
    }
    func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
        // Called when the user discards a scene session.
        // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
        // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
    }
}