object.Paint += new PaintEventHandler(Draw) hungs up everything

Question

Hello!
I have stucked on thes for few days already. My difference from examples is that I`m adding events to Paint dinamically. I`m not professional so I haven`t figured out how to redesign my code.
This is my code:
foreach(Part part in product.Parts)
{
    TabPage tabPage = new TabPage(part.FixedCode);

    tabPage.Name = part.FixedCode;
    tabPage.Size = tabPartCollection.Size;
    tabPage.Text = part.Name;
   
    DrawOnTabPage drawOnTabPage = new DrawOnTabPage();
    drawOnTabPage.LoadPart(part, product.MaxPartLength);

    tabPage.Paint += new PaintEventHandler(drawOnTabPage.Draw);

    tabPartCollection.Controls.Add(tabPage);
}

This foreach is called when pressing a form button. Class DrawOnTabPage contains method Draw which draws image on current TabPage. Everything works fine but when I move form outside my display it hungs up. The same is happening when I drag any other window over my application. CPU is 100% and this form takes all of it. As I understand there is redraw function called in this case. I have tried everything, disposing objects everywhere, setting specific styles but problem remains. Please help me!