Access of Undefined Property from a Class

[unrealhacker12]

package {
    import flash.display.MovieClip;
    import flash.events.Event;

    public class DumbClass extends MovieClip {
    
        var dumbXS:Number = 0;
        var dumbYS:Number = 0;
        var dumbACC:Number = 0.6;
        var dumbDEC:Number = 0.92;
        
        public function DumbClass() {
            this.addEventListener(Event.ENTER_FRAME, DumbMove);
        }

        public function DumbMove(evt:Event):void {
            //Increases Speed
            this.x += dumbXS;
            this.y += dumbYS;
            //Reference to a MovieClip on stage called "user".
            if (user.y < this.y) {
                dumbYS -= dumbACC;
            }
            //Reference to a MovieClip on stage called "user".
            if (user.y > this.y) {
                dumbYS += dumbACC;
            }
            //Reference to a MovieClip on stage called "user".
            if (user.x < this.x) {
                dumbXS -= dumbACC;
            }
            //Reference to a MovieClip on stage called "user".
            if (user.x > this.x) {
                dumbXS += dumbACC;
            }
            ///Decrease Speed
            dumbYS *= dumbDEC;
            dumbXS *= dumbDEC;
        }
    }
} 

I get an error that "user" is an undefined property even though its on the stage any ideas how I can fix this? :crying: