I cannot display any graphic on the watch face

I am trying to draw a circle in order to start to create an analogic watch face the digital time is showing but the circle is not showing.

This is my code:

function onUpdate(dc) {
        var clockTime = System.getClockTime();
        var timeString = Lang.format("$1$:$2$", [clockTime.hour, clockTime.min.format("%02d")]);
        var view = View.findDrawableById("TimeLabel") as WatchUi.Text;
        view.setText(timeString);
       
        View.onUpdate(dc);
       
        dc.setColor(Graphics.COLOR_RED, Graphics.COLOR_BLACK);
        dc.fillCircle(50, 100, 75);
        View.onUpdate(dc);
    }
Should I do anything else in other files?