C# program does not connect to a database (freesqldatabase.com)

Question

I'm using freesqldatabase.com to get a database for a college project, so having a remotely accessible database is needed. Unfortunately it does not connect to the database. It connects to their myphpadmin just fine but any other connection fails.

private void Submit_registration(object sender, RoutedEventArgs e)
{
    SqlConnection sqlCon = new SqlConnection(@"Data Source= sql2.freesqldatabase.com; Initial Catalog=dbname; User ID=id;Password=no, Integrated Security= True;");
    sqlCon.Open();

    String query = "INSERT INTO tbluser (ID, username, password) VALUES (@ID, @username, @password)";
    String query2 = "SELECT MAX(ID) FROM tbluser";

    SqlCommand cmd2 = new SqlCommand(query2, sqlCon);
    SqlCommand cmd = new SqlCommand(query, sqlCon);

    int maxId = Convert.ToInt32(cmd2.ExecuteScalar());
    int newmaxid = maxId + 1;

    if (String.Equals(text_password.Password,text_password_confirm.Password))
    {
        cmd.Parameters.AddWithValue("@ID", newmaxid.ToString());
        cmd.Parameters.AddWithValue("@username", textbox_username.Text);
        cmd.Parameters.AddWithValue("@password", text_password.Password);

        cmd.ExecuteNonQuery();
            
        sqlCon.Close();

        MainWindow mainWindow = new MainWindow();
        mainWindow.Show();
        Close();
    }
    else
    {
        MessageBox messageBox = new MessageBox();
        messageBox.Show();

        sqlCon.Close();
    }
}