1120: Access of undefined property contact.

Hey Im currently in the middle of designing a flash wesbite.. ive even followed a tutorial and im stillll having problems...when i create buttons and i want action script for those buttons to go to like home page and stuff i get that error message.. heres what my code looks like and pretty much looks the ame as it does on the tutorial aswell:s
//handle events for buttons...
video.addEventListener(MouseEvent.CLICK, clickSection);
home.addEventListener(MouseEvent.CLICK, clickSection);
photography.addEventListener(MouseEvent.CLICK, clickSection);
printdesign.addEventListener(MouseEvent.CLICK, clickSection);
pricelist.addEventListener(MouseEvent.CLICK, clickSection);
contact.addEventListener(MouseEvent.CLICK, clickSection);
function clickSection(evtObj:MouseEvent){
    //trace shows what's happening.. in the output window
    trace ("The "+evtObj.target.name+" button was clicked!")
    //go to the section clicked on...
i hope some 1 can help me with this... its just really unusual how im following the tutorial aswell and the code still aint working:s


Just check the frame label you have put is according to button name or not