pushRegistry(:didUpdate:for) not being called - ios

Question

I have looked at all questions about this but the answers to those have already been applied to my project but the pushRegistry() delegate method isn't getting invoked.
First here's the code:
import UIKit
import PushKit
#UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, PKPushRegistryDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
print("App Launched");
self.registerVoIPPush();
return true
}
func pushRegistry(_ registry: PKPushRegistry, didUpdate pushCredentials: PKPushCredentials, for type: PKPushType) {
print("didUpdate");
print(pushCredentials);
print(type);
if type == PKPushType.voIP {
let tokenData = pushCredentials.token
let voipPushToken = String(data: tokenData, encoding: .utf8)
print(voipPushToken);
//send token to server
}
}
func registerVoIPPush() {
print("registerVoIPPush");
let voipPushResgistry = PKPushRegistry(queue: DispatchQueue.main)
voipPushResgistry.delegate = self
voipPushResgistry.desiredPushTypes = [PKPushType.voIP]
}
func pushRegistry(_ registry: PKPushRegistry, didReceiveIncomingPushWith payload: PKPushPayload, for type: PKPushType) {
print(payload);
ATCallManager.shared.incommingCall(from: "jane#example.com", delay: 0)
}
}
I have also enabled following app capabilities: - Push Notifications -
Background Modes - Background Fetch - Remote Notifications - Voice
Over IP
I'm using Xcode11.3 & building using iOS13.2
On the provisioning portal Push Notifications have been enabled for the app id. (A VoIP Push cert has been generated & imported into keychain access as well but obviously can't use this to send the pushes yet).
Any help at all would be highly appreciated as I am trying to get this done since last 3 days.

Answer 1

Your PKPushRegistry object is deallocated as soon as registerVoIPPush() method is finished
Check if you set up appropriate background mode