private void SaveBillingCycle()
        {
            if (!Page.IsValid)
            {
                return;
            }

            try
            {
                string cycleName     = txtCycleName.Text.Trim();
                string billingPeriod = ddlBillingPeriod.SelectedValue.Trim();
                int    periodLength  = Convert.ToInt32(txtPeriodLength.Text.Trim());

                int result = StorehouseHelper.UpdateBillingCycle(ecPanelRequest.BillingCycleId, cycleName, billingPeriod, periodLength);

                if (result < 0)
                {
                    ShowResultMessage(result);
                    return;
                }
            }
            catch (Exception ex)
            {
                // show error
                ShowErrorMessage("BILLING_CYCLE_SAVE", ex);
                return;
            }

            RedirectToBrowsePage();
        }