Debugging with println / console?

Hi,

I want to use println for debugging in the console but no output there.

What can be reason?

 function onUpdate(dc as Dc) as Void {
        // Call the parent onUpdate function to redraw the layout
        View.onUpdate(dc);
              System.println("hello world");

Also initialized with "import Toybox.System";

It is used in source...view.mc