usercontrols visible not visibles are not working

namespace JSPROYECTOBD
{
    public partial class MainForm : Form
    {
        public tablasydatos tablasydatos;
        public flujo flujo;
        private bool dragging = false;
        private Point dragCursorPoint;
        private Point dragFormPoint;

        public MainForm()
        {
            InitializeComponent();
            tablasydatos = new tablasydatos();
            flujo = new flujo();

            this.Controls.Add(tablasydatos);
            this.Controls.Add(flujo);
            tablasydatos.Visible = true;
            flujo.Visible = false;
        }

        private void tablasydatos1_Load(object sender, EventArgs e)
        {

        }


        private void panel1_MouseUp(object sender, MouseEventArgs e)
        {
            dragging = false;
        }

        private void label1_Click(object sender, EventArgs e)
        {Application.Exit();}
        private void button1_Click(object sender, EventArgs e)
        {
            tablasydatos.Visible = true;
            flujo.Visible = false;
        }

        private void flujogananciabtn_Click(object sender, EventArgs e)
        {
            flujo.Visible = true;
            tablasydatos.Visible = false;
        }}}