DrawF***

I'm really, really bad at making drawings. As a child, as an adult and even as a programmer. Why, oh why, won't my simple robot draw a simpe line. It just doesn't. It won't draw text either.

private void tekenLijnen(int mc, int bc)
{
    ChartObjects.DrawLine("hoog_" + mc.ToString(), mc, MarketSeries.High[mc], bc, MarketSeries.High[mc], Colors.AliceBlue, 2, LineStyle.Solid);
    ChartObjects.DrawLine("laag_" + mc.ToString(), mc, MarketSeries.Low[mc], bc, MarketSeries.Low[mc], Colors.Coral, 2, LineStyle.Solid);
}

What am i doing wrong? The indices mc and bc are close to the latest bar (MarketSeries.Low.Count-1).

Help...