Mein Programm ist zwar vollständig, aber beim Start fängt es sich nicht an zu bewegen, sondern bleibt gefreezed.

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Pong_the_Game
{
  public partial class Form1 : Form
  {
    public int speed_left = 4; // ball speed
    public int speed_top = 4;
    public int Point = 0;

    public Form1()
    {
      InitializeComponent();

      timer1.Enabled = true;
      Cursor.Hide();
      this.FormBorderStyle = FormBorderStyle.None; // wegmachen der Border
      this.TopMost = true; //form im vordergrund
      this.Bounds = Screen.PrimaryScreen.Bounds; // Fullscreen
      
      Brett.Top = Playground.Bottom - (Playground.Bottom / 10); // Position vom Brett
    }

    private void timer1_Tick(object sender, EventArgs e)
    {
      Brett.Left = Cursor.Position.X - (Brett.Width / 2); // macht das Brett als Cursor
      Ball.Left += speed_left;   // bewegt den Ball
      Ball.Top += speed_top;

      if (Ball.Bottom >= Brett.Top && Ball.Bottom <= Brett.Bottom && Ball.Left >= Brett.Left && Ball.Right <= Brett.Right) // Kollision
      {
        speed_top += 2;
        speed_left += 2;
        speed_top = -speed_top; // tauscht Beschreibeung
        Point += 1;
      }

      if (Ball.Left <= Playground.Left)
      {
        speed_left = -speed_left;
      }

      if (Ball.Right <= Playground.Right)
      {
        speed_left = -speed_left;
      }

      if (Ball.Left <= Playground.Top)
      {
        speed_top = -speed_top;
      }

      if (Ball.Bottom <= Playground.Bottom)
      {
        timer1.Enabled = false; // wenn der Ball ins unten raus ist, stoppt das Spiel
      }
    }

    private void Form1_KeyDown(object sender, KeyEventArgs e)
    {
      if (e.KeyCode == Keys.Escape) // Esc drücken für Verlassen
      {
        this.Close();
      }
    }

    private void pbr_Click(object sender, EventArgs e)
    {
    }

    private void pbb_Click(object sender, EventArgs e)
    {
    }
  }
}