private void btnSaveBill_Click(object sender, EventArgs e)
        {
            if (billObj.dtBillDetails.Rows.Count == 0)
            {
                XtraMessageBox.Show("No items to draft", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                return;
            }

            DataSet nextBillDetails = billingRepository.DraftBill(Utility.logininfo.UserID, daySequenceID, billObj.BillID);

            LoadBillData(nextBillDetails);
        }