private void Button_DeleteReservation(object sender, RoutedEventArgs e)
        {
            var            viewModel           = (ReservationViewModel)DataContext;
            var            client              = new AutoReservationServiceClient();
            ReservationDto selectedReservation = client.getReservationByNr(viewModel.SelectedReservation.ReservationsNr);

            client.removeRerservation(selectedReservation);
        }