Automated Email Notifications in ASP.Net not triggered

Hello Sir,

Below is the code which I'm using to triggere automated Emails from web application.

Thanks

  try
        {
            SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["CRM_DB"].ConnectionString);
            DataTable dt = new DataTable();
            string query = "SELECT staffname, email,driving_date FROM documents WHERE DATEPART(DAY, driving_date) = @Day AND DATEPART(MONTH, driving_date) = @Month";
            SqlCommand cmd = new SqlCommand(query);

            cmd.Connection = con;
            cmd.Parameters.AddWithValue("@Day", DateTime.Today.Day);
            cmd.Parameters.AddWithValue("@Month", DateTime.Today.Month);
            using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
            {
                sda.Fill(dt);

            }

            for (int i = 0; i < dt.Rows.Count; i++)
            {

                // Checking condition of Current Date with Database Date.
                if (Convert.ToDateTime(dt.Rows[i]["driving_date"]).AddDays(-1).ToShortDateString() == DateTime.Now.ToShortDateString())
                {
                    using (MailMessage mailMessage = new MailMessage())
                    {
                        mailMessage.From = new MailAddress("myemail@gmail.com");
                        mailMessage.Subject = "Test Subject";
                        mailMessage.Body = "Test Body";
                        mailMessage.IsBodyHtml = true;
                        mailMessage.To.Add(new MailAddress(dt.Rows[i]["email"].ToString()));
                        SmtpClient smtp = new SmtpClient();
                        smtp.Host = "smtp.gmail.com";
                        smtp.EnableSsl = true;
                        System.Net.NetworkCredential NetworkCred = new System.Net.NetworkCredential();
                        NetworkCred.UserName = "mymail@gmail.com";
                        NetworkCred.Password = "password";
                        smtp.UseDefaultCredentials = true;
                        smtp.Credentials = NetworkCred;
                        smtp.Port = 587;
                        smtp.Send(mailMessage);
                        Response.Redirect("Mail sent");
                    }
                }
                else{
                    Response.Redirect("Mail not sent");
                    }
            }
        }
        finally
        {
            con.Close();
            con.Dispose();
        }

 void Application_Start(object sender, EventArgs e) 
    {
        // Code that runs on application startup
        System.Timers.Timer timer = new System.Timers.Timer();
        // Set the Interval to 7 Days (604800000 milliseconds).
        timer.Interval = ((((1 * 24) * 60) * 60) * 1000);
        timer.AutoReset = true;
        timer.Elapsed += new System.Timers.ElapsedEventHandler(TimerElapsed);
        timer.Enabled = true;
    }
    public void TimerElapsed(object source, System.Timers.ElapsedEventArgs e)
    {
        // Instanciate the Mail class.
        ScheduleMail scheduleMail = new ScheduleMail();
        // Call the send mail method.
        scheduleMail.SendScheduleMail();
    }