private async void button9_Clicked(object sender, EventArgs e)
{
    button9.IsEnabled = false;
    try
    {
        if (!await MercatorPenguin.Dialogs.AnswerYesNo(this, $"Wil je echt een verkoop (concept) aanmaken voor klant {DataTable.Rows[0]["c_nom"]}?"))
            return;
        await EditBilling(new MercatorPenguin.Classes.EditBillingDescriptor(this, activityIndicator)
        {
            BillingTypeVA = MercatorPenguin.Enums.TypeVAEnum.V,
            BillingJournal = "Brou",
            BillingId = "",
            BillingPiece = 0,
            BillingType = 7,
            DefaultValues = [new MercatorPenguin.Classes.ItemDefaultValue { ColumnName = "ID_CLI", Value = DataTable.Rows[0]["c_id"].ToString() }]
        });
    }
    finally
    {
        button9.IsEnabled = true;
    }
}