I Want To Integrate Mobile Recharge Api In Asp.Net With C# I Have Written a Program But It Is Not Working Properly Some One Can Help Me.

using System;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.IO;
using System.Net;

public partial class _Default : System.Web.UI.Page 
{
    
      
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        SendMsg();
        
       

    }
     public void SendMsg()
        {
         Label1.Text = "domain name";
            string uid= " 72656368617267656e657374 ";
            string pin = " 52c29795bc54d";
            string sender = "Your Sender ID";
	    string route = "1";
        string message = "scussfully recharge ";
            string mobile = TextBox1.Text;
            string amount = TextBox2.Text;
	    string domain = Label1.Text;
        string url = "http://" + domain + "/api/sms.php?uid=" + uid + "&pin=" + pin + "&sender=" + sender + "&route=" + route + "&mobile=" + mobile + "&amount=" + amount + "&message=" + message;


            HttpWebRequest httpreq = (HttpWebRequest)WebRequest.Create(url);
            try
            {
                HttpWebResponse httpres = (HttpWebResponse)httpreq.GetResponse();
                StreamReader sr = new StreamReader(httpres.GetResponseStream());
                string results = sr.ReadToEnd();
                sr.Close();
            }
            catch (Exception ex)
            {
                
            }
        }
   
}