ZPNs Error Codes
The ZPNs iOS error codes are provided directly by Apple. Please pay attention to the delegate method didFailToRegisterForRemoteNotificationsWithError:. For more details, refer to the Apple Official Documentation.
- (void)application:(UIApplication *)application didFailToRegisterForRemoteNotificationsWithError:(NSError *)error API_AVAILABLE(ios(3.0)){
    // Handle the NSError accordingly
}


