Thanks but I give up!!!
I followed your advice to the letter and still I just can't get it to work and I have been on this for a week, so I'm giving up.
At least, I got the coupon to work and I have just used a spry tooltip to help users identify any errors.
I don't know why I can't get the other part to work and now I have become confused as to what is meant to be done with it.