how could i store information in database and redirect page

Question

Here is my code and when i fill all required fields it will not navigate to another page! what is the error and i want to check if email is already exist it will show error message Email already exists

 protected void btnRegister_Click(object sender, EventArgs e)

        {

              SqlConnection myConnection = new SqlConnection(@"Data Source=ALIASHIQ\SQL2013;Initial Catalog=Person;Integrated Security=True");

            SqlCommand cmd = new SqlCommand("INSERT INTO UserData(FirstName,LastName,Email,Mobile,Address,Password) VALUES (@Name,@LastName,@Email,@Mobile,@Address,@Password)", myConnection);

            cmd.CommandType = CommandType.Text;

            //if (txtEmail.Text == txtEmail.Text)

          //  {

                cmd.Parameters.AddWithValue("@Name", txtName.Text);

                cmd.Parameters.AddWithValue("@LastName", txtLastName.Text);

                cmd.Parameters.AddWithValue("@Email", txtEmail.Text);

                cmd.Parameters.AddWithValue("@Mobile", txtMobile.Text);

                cmd.Parameters.AddWithValue("@Address", txtAddress.Text);

               cmd.Parameters.AddWithValue("@Password", txtPassword.Text);

       //      cmd.Parameters.AddWithValue("@Password", txtPassword.Text);

                myConnection.Open();

                cmd.ExecuteNonQuery();

                myConnection.Close();

                Response.Redirect("contenctwelcome.aspx");

            //}

            //else 

            //{ 

            //    ErrorMessage.Text = "Please enter all fields"; 

            //}