public async void SendInvoiceMerchant(string customerPhone, string customerEmail, string customerName, string amount, string paymentDescription, string transactionId, string PayUMoneyURL)
        {
            List <KeyValuePair <string, string> > Parameters = new List <KeyValuePair <string, string> >();

            Parameters.Add(new KeyValuePair <string, string>("customerPhone", customerPhone));
            Parameters.Add(new KeyValuePair <string, string>("customerEmail", customerEmail));
            Parameters.Add(new KeyValuePair <string, string>("customerName", customerName));
            Parameters.Add(new KeyValuePair <string, string>("amount", amount));
            Parameters.Add(new KeyValuePair <string, string>("paymentDescription", paymentDescription));
            Parameters.Add(new KeyValuePair <string, string>("transactionId", transactionId));
            try
            {
                HttpResponseMessage response = await WebApiReq.PostReqPayUMoney("payment/payment/addInvoiceMerchantAPI?", Parameters, "", "", _appSettings.payurl, _appSettings.AuthorizationKey);

                if (response.IsSuccessStatusCode)
                {
                    Redirect(response.RequestMessage.RequestUri.OriginalString);
                }
            }
            catch (Exception ex)
            {
            }
        }