[Solved] ASP.Net ExecuteNonQuery Error: Must declare scalar variable

I am getting an error  "Must declare scalar variable @id" but I can't find where I am wrong.

Thanks

        protected void Page_Load(object sender, EventArgs e)
        {
            
                string constr = ConfigurationManager.ConnectionStrings["Q_SS_regnConnectionString1"].ConnectionString;
                SqlConnection con = new SqlConnection(constr);
                SqlCommand cmd2 = new SqlCommand("select * from JS_Resume where CompanyEmail='" + Session["mail"].ToString() + "' and Status='UnApproved'", con);
                SqlDataAdapter da = new SqlDataAdapter(cmd2);
                DataTable dt = new DataTable();
                da.Fill(dt);
                GridView2.DataSource = dt;
                GridView2.DataBind();
            
            if (Request.QueryString["Id"] != null)
            {
                var Id = Request.QueryString["Id"];
                var email = Request.QueryString["email"];
                //var Password = Request.QueryString["Password"];
                try
                {
                    SqlCommand cmd = new SqlCommand("update JS_Resume set status='Approved' where Id=@id", mycon);
                    cmd.Parameters.AddWithValue("@id", Id);
                    //Response.Write(U_id);
                    mycon.Open();
                    cmd.ExecuteNonQuery();
                    cmd.Parameters.Clear();
                    cmd.ExecuteNonQuery();
                    ClientScript.RegisterStartupScript(GetType(), "alert", "alert('Approved.');", true);
                }
                catch (Exception ex)
                {
                    Response.Write(ex);
                    ClientScript.RegisterStartupScript(GetType(), "alert", "alert('Not Approved.');", true);
                }
                finally
                {
                    mycon.Close();
                }
                try
                {
                    SqlCommand cmd = new SqlCommand("select * from JS_Resume where Id=@id and CompanyEmail='" + Session["mail"].ToString() + "'", mycon);
                    cmd.Parameters.AddWithValue("@id", Id);
                    cmd.CommandType = System.Data.CommandType.Text;
                    cmd.Connection = mycon;
                    mycon.Open();
                    SqlDataReader dar = cmd.ExecuteReader();
                    if (dar.Read())
                    {
                        Id = dar["Id"].ToString();
                        email = dar["email"].ToString();
                        //Password = dar["Password"].ToString();
                        using (MailMessage mm = new MailMessage("jobopediaHere@gmail.com", email))
                        {
                            mm.Subject = "Resume Approved";
                            mm.Body = "Congratulations..!!\nYour Resume has been Approved.\nYour Username: " + email + "\n For Further Process Company Will Contact You By Your Registered Email or Phone.\nThank you For Connecting With Us.";
                            mm.IsBodyHtml = false;
                            SmtpClient smtp = new SmtpClient();
                            smtp.Host = "smtp.gmail.com";
                            smtp.EnableSsl = true;
                            NetworkCredential NetworkCred = new NetworkCredential("xyz@gmail.com", "123");
                            smtp.UseDefaultCredentials = true;
                            smtp.Credentials = NetworkCred;
                            smtp.Port = 587;
                            smtp.Send(mm);
                            ClientScript.RegisterStartupScript(GetType(), "alert", "alert(' Email Sent.');", true);
                        }
                    }
                }
                catch (Exception)
                {
                    //Response.Write(ex.ToString());
                }
                finally
                {
                    //Label1.Text = ("message sent");
                }
            }
        }