Update XML using forms

[admin]

im trying to update my XML file using forms. But when i click submit it just refreshs the page but nothing is written to the xml file. Please help!

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

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

}
protected void Submit_Click(object sender, EventArgs e)
{
string date_now = DateTime.Now.Month.ToString() + "/" + DateTime.Now.Day.ToString() + "/" + DateTime.Now.Year.ToString();

string cheese = date_now + " " + address.Text + " " + borrower.Text;
BulletedList1.Items.Add(cheese);

XmlTextWriter writer = new XmlTextWriter("closings.xml", null);

//Start an element
writer.WriteStartElement("date");

//Add an attribute to the previously created element
writer.WriteAttributeString("cdate", date_now);

//add sub-elements
writer.WriteElementString("address", address.Text);
writer.WriteElementString("borrower", borrower.Text);
writer.WriteElementString("olender", olender.Text);
writer.WriteElementString("type", dropdown1.SelectedItem.Text);
writer.WriteElementString("investor", CheckBoxList1.SelectedItem.Text);

//End the date element
writer.WriteEndElement(); // end element date

//Write some white space between nodes
writer.WriteWhitespace("\n");

//Write the XML to file and close the writer
writer.Close();

}
}