jQuery Modal Popup TextBox values Empty (Blank) when using ASP.Net UpdatePanel

Update Query not updating on Button Click in Modal Popup.

Any Field i update will go blank.

Please help.

My code

    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
    <script type="text/javascript" src="https://cdn.datatables.net/1.10.20/js/jquery.dataTables.min.js"></script>
    <link href="https://cdn.datatables.net/1.10.20/css/jquery.dataTables.css" rel="stylesheet" type="text/css" />
    <link rel="stylesheet" href="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.24/themes/smoothness/jquery-ui.css" />
    <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.8.24/jquery-ui.min.js"></script>
    <script type="text/javascript">
        $(function () {
            $(".grid").DataTable({
                bLengthChange: true,
                lengthMenu: [[10, 30, -1], [10, 30, "All"]],
                bFilter: true,
                bSort: true,
                bPaginate: true
            });
        });
        function ShowPopup() {
            $("#dialog").dialog({
                title: "VIEW DIE DETAILS",
                width: 830,
                height: 500,
                buttons: {
                    Close: function () {
                        $(this).dialog('close');
                    }
                },
                modal: true
            });
        };

        function ShowPopup1() {
            $("#dialog1").dialog({
                title: "EDIT  DIE DETAILS",
                width: 830,
                height: 500,
                buttons: {
                    Close: function () {
                        $(this).dialog('close');
                    }
                },
                modal: true
            });
        };
    </script>
        <script type="text/javascript">
            var prm = Sys.WebForms.PageRequestManager.getInstance();
            if (prm != null) {
                prm.add_endRequest(function (sender, e) {
                    if (sender._postBackSettings.panelsToUpdate != null) {
                        $(".grid").DataTable({
                            bLengthChange: true,
                            lengthMenu: [[10, 30, -1], [10, 30, "All"]],
                            bFilter: true,
                            bSort: true,
                            bPaginate: true
                        });
                    }
                });
            };
        </script>

public partial class Die : System.Web.UI.Page
{
    protected void ImageButton1_Click(object sender, object e)
    {
            updateSQL = "UPDATE job_die set ";
            updateSQL += "dieno=@dieno,templateno=@templateno,model=@model,type=@type,brassfemaleembossin=@brassfemaleembossin,";
            updateSQL += "brassmaleembossing=@brassmaleembossing,supplier=@supplier,lcutterwidth=@lcutterwidth,lcutterlength=@lcutterlength,comment=@comment,";
            updateSQL += "lmacross=@lmacross,lmaround=@lmaround,caditemidno=@caditemidno,cadrefno=@cadrefno ,cadnoups=@cadnoups,cadpackheight=@cadpackheight,";
            updateSQL += "cadpackwidth=@cadpackwidth,cadpackbreadth=@cadpackbreadth,caddesignheight=@caddesignheight,caddesignwidth=@caddesignwidth,cadgripperwidth=@cadgripperwidth ,";
            updateSQL += "cadgripperlenth=@cadgripperlenth,cadchargenno=@cadchargenno  WHERE id=@id ";
            // updateSQL += "";
            dbConn2.ConnectionString = "Data source=Graden\\EXPRESS01; Initial Catalog=Household;Integrated Security=True;";
            cmd1.Connection = dbConn2;
            cmd1.CommandText = updateSQL;
            cmd1.CommandType = CommandType.Text;
            cmd1.Parameters.AddWithValue("@dieno", TextBox1.Text);
            cmd1.Parameters.AddWithValue("@templateno", TextBox2.Text);
            cmd1.Parameters.AddWithValue("@model", TextBox3.Text);
            cmd1.Parameters.AddWithValue("@type", TextBox4.Text);
            cmd1.Parameters.AddWithValue("@brassfemaleembossin", TextBox5.Text);

            cmd1.Parameters.AddWithValue("@brassmaleembossing", TextBox6.Text);
            cmd1.Parameters.AddWithValue("@supplier", TextBox7.Text);
            cmd1.Parameters.AddWithValue("@lcutterwidth", TextBox8.Text);
            cmd1.Parameters.AddWithValue("@lcutterlength", TextBox9.Text);
            cmd1.Parameters.AddWithValue("@comment", TextBox10.Text);
            cmd1.Parameters.AddWithValue("@lmacross", TextBox11.Text);
            cmd1.Parameters.AddWithValue("@lmaround", TextBox12.Text);
            cmd1.Parameters.AddWithValue("@caditemidno", TextBox13.Text);
            cmd1.Parameters.AddWithValue("@id", Session["sid"].ToString());
            cmd1.Parameters.AddWithValue("@cadrefno", TextBox14.Text);
            cmd1.Parameters.AddWithValue("@cadnoups", TextBox15.Text);
            cmd1.Parameters.AddWithValue("@cadpackheight", TextBox16.Text);
            cmd1.Parameters.AddWithValue("@cadpackwidth", TextBox17.Text);
            cmd1.Parameters.AddWithValue("@cadpackbreadth", TextBox18.Text);

            cmd1.Parameters.AddWithValue("@caddesignheight", TextBox19.Text);
            cmd1.Parameters.AddWithValue("@caddesignwidth", TextBox20.Text);
            cmd1.Parameters.AddWithValue("@cadgripperwidth", TextBox21.Text);
            cmd1.Parameters.AddWithValue("@cadgripperlenth", TextBox22.Text);
            cmd1.Parameters.AddWithValue("@cadchargenno", TextBox23.Text);

            try
            {
                dbConn2.Open();
                Response.Write(updateSQL);
                int updated = cmd1.ExecuteNonQuery();
                //    Response.Write(updateSQL);
                Label71.Visible = true;
                Label71.Text = updated.ToString() + " records updated.";
                // Response.Redirect("~/Thanku.aspx");
            }

            //catch (Exception err)
            //{
            //    Label1K.Text = "Error  updating record";
            //    Label1K.Text += err.Message;
            //}
            finally
            {
                dbConn2.Close();
            }
        }
    }