private void UserControl_Loaded(object sender, RoutedEventArgs e)
        {

            if (DataContext is Biller.UI.ViewModel.MainWindowViewModel)
            {
                var settings = new Biller.Core.Database.AppSettings();
                settings.Database = "538BAA9C-D630-486D-BD61-02706C09E2A9";
                settings.Save();
            }
        }