Форма отстает от курсора

private void CheckWin()
{
    bool a = true;
    for (int i = 0; i < 900; i++)
    {
        if (mass2[i] != mass[i])
        {
            a = false;
        }
    }
    if (a)
    {
        panel1.Visible = false;
        panel2.Size = new Size(937, 1073);
        panel2.Location = new Point(12, 12);
        panel2.Controls.Add(label13);
        label13.Text = "Вы победили!";
        label13.AutoSize = false;
        label13.Dock = DockStyle.Fill;
        label13.TextAlign = ContentAlignment.MiddleCenter;
        panel2.Visible = true;
    }
}

int
DX = 150,
DY = 30,
HeightP = 25,
WidthP = 25,
PictureBox PictureBox1 = new PictureBox()
{
    Height = 750,
    Width = 750,
    Location = new Point(DX, DY)
};
panel1.Controls.Add(PictureBox1);
var dst = new Rectangle(150, 25, HeightP, WidthP);
var source = Resources.blank;
using (var gfx = PictureBox1.CreateGraphics())
{
    gfx.DrawImage(source, 0,0,25,25);
}

Bitmap buf=new Bitmap(750,750);
Graphics gfx = Graphics.FromImage(buf);
gfx.DrawImage(Resources.full, X*25, Y*25, 25, 25);
pictureBox1.Image = buf;

Graphics gfx = Graphics.FromImage(pictureBox1.Image);
gfx.DrawImage(Resources.full, X*25, Y*25, 25, 25);
pictureBox1.Invalidate();

public partial class Form1 : Form
{
Bitmap buf=new Bitmap(750,750);
Graphics gfx;
 
public Form1()
{
    InitializeComponent();
 
    gfx = Graphics.FromImage(buf);
}
 
private void pictureBox_ClickMouse(int X,int Y, int Button)
{            
    gfx.DrawImage(Resources.full, X*25, Y*25, 25, 25);
    pictureBox1.Image = buf;
}
}

public partial class Form1 : Form
{
    private Bitmap buf;
    private Graphics gfx;
 
    public Form1()
    {
        InitializeComponent();
 
        buf = new Bitmap(750, 750);
        pictureBox1.Image = buf;
        gfx = Graphics.FromImage(buf);
    }
 
    private void pictureBox_ClickMouse(int X, int Y, int Button)
    {
        gfx.DrawImage(Resources.full, X * 25, Y * 25, 25, 25);
    }
 
    protected override void Dispose(bool disposing)
    {
        base.Dispose(disposing);
 
        buf.Dispose();
        gfx.Dispose();
    }
}

public partial class Form1 : Form
{
    private Bitmap buf;
    private Graphics gfx;
 
    public Form1()
    {
        InitializeComponent();
 
        buf = new Bitmap(750, 750);
        pictureBox1.Image = buf;
        gfx = Graphics.FromImage(buf);
        Disposed += (_, __) => 
        {
            buf.Dispose();
            gfx.Dispose();
        };
    }
 
    private void pictureBox_ClickMouse(int X, int Y, int Button)
    {
        gfx.DrawImage(Resources.full, X * 25, Y * 25, 25, 25);
        pictureBox1.Refresh();
    }
}