Как добавить динамические элементы на статичную панель?

Есть статичная панель на нее добавляю динамически элементы и ловлю исключение:

System.NullReferenceException: "Ссылка на объект не указывает на экземпляр объекта."

panel2 было null.

private void PaintElement(string patchImage, string typeAgent, string nameAgent, string sales, string phone, string priority, string percent)
{

Panel otstup = builder.CreatePanel(height: 20, border: BorderStyle.None);
Panel osnova = builder.CreatePanel(130);
FlowLayoutPanel leftToRight = builder.CreateFlowLayoutPanel(FlowDirection.LeftToRight);

PictureBox picture = builder.CreatePictureBox(patchImage);


FlowLayoutPanel DockRight = builder.CreateFlowLayoutPanel(FlowDirection.LeftToRight, Dock = DockStyle.Right);
Label labelPercent = builder.CreateLabel(percent.ToString(), 14.25F);
DockRight.Controls.Add(labelPercent);

//Панель с label:ами
FlowLayoutPanel topToDown = builder.CreateFlowLayoutPanel(FlowDirection.TopDown);
FlowLayoutPanel leftToRightLabel = builder.CreateFlowLayoutPanel(FlowDirection.LeftToRight);
Label labelNameAgent = builder.CreateLabel(nameAgent, 14.25F);
Label labelTypeAgent = builder.CreateLabel(typeAgent, 14.25F);
Label labelSales = builder.CreateLabel(sales, 12F);
Label labelPhone = builder.CreateLabel(phone, 12F);
Label labelPriority = builder.CreateLabel(priority, 12F);
leftToRightLabel.Controls.Add(labelTypeAgent);
leftToRightLabel.Controls.Add(labelNameAgent);
topToDown.Controls.Add(leftToRightLabel);
topToDown.Controls.Add(labelSales);
topToDown.Controls.Add(labelPhone);
topToDown.Controls.Add(labelPriority);

leftToRight.Controls.Add(picture);
leftToRight.Controls.Add(topToDown);

osnova.Controls.Add(leftToRight);
osnova.Controls.Add(DockRight);

panel2.Controls.Add(osnova);
panel2.Controls.Add(otstup);
}

private void LoadElement()
{
    Random rnd = new Random();
    string percent;

for (int i = 1; i <= agents.Count; i++)
{
    percent = rnd.Next(0, 70).ToString() + "%";
    PaintElement(agents[i - 1][0], agents[i - 1][1] + " |", agents[i - 1][2], agents[i - 1][3], agents[i - 1][4], agents[i - 1][5], percent);
}
}