public void RegisterUserNotificationCategories(NotificationUserCategory[] userCategories)
        {
            UserNotificationCategories.Clear();

            foreach (NotificationUserCategory userCategory in userCategories)
            {
                UserNotificationCategories.Add(userCategory);
            }
        }
 public NotificationUserCategory[] GetUserNotificationCategories()
 {
     return(UserNotificationCategories?.ToArray());
 }