c # – Slowness when creating dynamic maskedTextBox

I have a project that when I want to add, for example, a matrix of maskedTextBox of 21×21 within a groupBox makes it slow … I would like to know if this is something normal because I am instantiating resources in execution time or is there a way to do it without it being so slow … Here I leave the instance code of maskedTextBox

// itero by the rows and columns
for (int i = 1; i <= M - 1; i ++)
{
     BtnAddFila_Click (sender, e);
}
for (int i = 1; i <= N - 1; i ++)
{
     BtnAddCol_Click (sender, e);
}
private void BtnAddCol_Click (object sender, EventArgs e)
    {
        int x, y;
        y = textBoxesMatrix[0, indF].Location.Y;
        x = textBoxesMatrix[0, indF].Location.X + 35;


        btnAddFila.Location = new Point (x + 30, y);

        indF ++;

        for (int i = 0; i <= indC; i ++)
        {
            y = textBoxesMatrix[i, indF - 1].Location.Y;
            x = textBoxesMatrix[i, indF - 1].Location.X + 35;
            MaskedTextBox maskedTextBoxFilaNew = new MaskedTextBox
            {
                Text = "",
                Mask = maskedTextBoxFila.Mask,
                Location = new Point (x, y),
                Visible = true,
                Height = maskedTextBoxFila.Height,
                Width = maskedTextBoxFila.Width,
                Enabled = true,
                BeepOnError = true,
                TextAlign = HorizontalAlignment.Right,
                Parent = matrixGroupBox
            };

            textBoxesMatrix[i, indF] = maskedTextBoxFilaNew;
        }
  }

The other button does exactly the same … Any suggestions ??