doesn't work

all of the offers has to be loaded otherwise it doesn't work. I don't wont to remember this. I would prefer those offers to be added to the card automatically and to be informed by the cashier or maybe by an email.
I did get an offer for my birthday month and went to the tills to pay and even I had this offer loaded it didn't work so I had to ask someone to fix it on the tills. So I don't understand. If I want load the offer it doesn't work but when I will it's still doesn't work. What is the point?