UNNotification: Custom Sound for LocalNotification is not playing in iOS10

I'm firing a local notification. Since `UILocalNotification` class is deprecated in iOS 10, I have used `UserNotifications.framework`. When I try to set the custom sound for the notification, the default sound is playing all time. Here is my code: ``` - (IBAction)fireLocalNotification:(id)sender { UNMutableNotificationContent* content = [[UNMutableNotificationContent alloc] init]; content.title = [NSString localizedUserNotificationStringForKey:@"Hello!" arguments:nil]; content.body = [NSString localizedUserNotificationStringForKey:@"Hello_message_body" arguments:nil]; content.sound = [UNNotificationSound soundNamed:@"sound.mp3"]; // Deliver the notification in five seconds. UNTimeIntervalNotificationTrigger* trigger = [UNTimeIntervalNotificationTrigger triggerWithTimeInterval:5 repeats:NO]; UNNotificationRequest* request = [UNNotificationRequest requestWithIdentifier:@"FiveSecond" content:content trigger:trigger]; // Schedule the notification. UNUserNotificationCenter* center = [UNUserNotificationCenter currentNotificationCenter]; [center addNotificationRequest:request withCompletionHandler:^(NSError *error){ if(!error){ NSLog(@"Completion handler for notification"); } }]; } ``` My sound is fine; sound.mp3 is present in project bundle itself. More info: https://developer.apple.com/reference/usernotifications/unusernotificationcenter?language=objc