Store card

I have app**** for a Pick n Pay store card, on the web page they advertise that for the first purchase, you will receive R200 off from a purchase of more than R500. The cashier said that they cannot deduct the amount, I have to phone the accounts department. I have spoken with three consultants but the deduction was not made, I received my statement and the full amount is on the statement. I wanted to know whether there are other buyers that experience the same service?