I dont update value in textbox

private void Bindload()
    {
        lbl_cat.Visible = false;
        if (Session["user"] != null)
        {
            string constr = ConfigurationManager.ConnectionStrings["name"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand("SELECT  id_house_manager,name_house_manager,username_house_manager,name_house_manager from tbl where username_house_manager  ='" + Session["user"] + "'", con))
                {
                    con.Open();
                    SqlDataReader reader = cmd.ExecuteReader();
                    while (reader.Read())
                    {
                        lbl_cat.Text = reader["id_house_manager"].ToString();
                        lbl_id.Text = reader["name_house_manager"].ToString();
                        txt_name.Text = reader["name_house_manager"].ToString();
                        Session["id"] = lbl_cat.Text;
                    }
                }
            }
        }
        else
        {
            Session.RemoveAll();
            Response.Redirect("/Default.aspx");
        }
        if (!IsPostBack)
        {
        }
    }    







protected void btn_update_Click(object sender, EventArgs e)
    {


        string cs = ConfigurationManager.ConnectionStrings["name"].ToString();
        using (SqlConnection con = new SqlConnection(cs))
        {
            con.Open();
            using (SqlCommand cmd = new SqlCommand("UPDATE [db].[dbu].[tbl_house_manager] SET [name_house_manager] = @name_house_manager WHERE [username_house_manager] ='" + Session["user"] + "'", con))
            {
                cmd.Parameters.AddWithValue("@name_house_manager", txt_name.Text);

                cmd.ExecuteNonQuery();
                lbl_alert.Text = "thanks";  //after Sucessfully uploaded image
                con.Close();


            }
        }
    }

[edit]Code block added - OriginalGriff[/edit]