My Clock Won't Count Down?

I used the tutorial, but my clock still won’t count down …any help? suggestions???
here’s the script, it is just like on the tutorial…Help !

_root.onEnterFrame + function() {
var myDate = new Date();
var myHours = myDate.getHours();
var myMinutes = myDate.getMinutes();
var mySeconds = myDate.getSeconds();
var AmPm;
if (myHours < 12){
AmPm = “AM”;
}
else
{
AmPm = “PM”;
}
if (myHours == 0) {
myHours = 12;
}
if (myHours > 12) {
myHours = myHours - 12;
}
if (myHours <10) {
myHours = “0” + myhours;
}
if (myMinutes < 10) {
myMinutes = “0” + myMinutes;
}
if (mySeconds < 10) {
mySeconds = “0” + mySeconds;
}
time_txt.text = myHours + “:” + myMinutes + “:” + mySeconds + " " + AmPm;
}