TypeError: Error #1007: Instantiation attempted on a non-constructor

1

hello. need some help ASAP.
what i’m trying to do is get a movie to duplicate movieclips when the original movieclip is dropped onto a target.
what it does is,

  1. click, drag movie clip to target.
  2. drop, released.
  3. duplicate movieclip appears in the ORIGINAL position from where the original movieclip was picked up.
  4. and keep the dropped movieclip in place.

i don’t know why i get,

TypeError: Error #1007: Instantiation attempted on a non-constructor. at Untitled_fla::MainTimeline/dirt_UP()



function dirt_UP(e:MouseEvent):void{




  
  if (e.target.dropTarget != null && e.target.dropTarget.parent == this.shirt){ e.target.stopDrag();

startX = e.target.x;
startY = e.target.y;

var dirt_rock:MovieClip = new e.target.duplicateMovieClip();
    
addChild(dirt_rock);




dirt_rock.x = startX;
dirt_rock.y = startY;
}