Cappuccino subscription at Mugg and Bean

I app**** for the 10 coffees/cappuccinos subscription. When ordering my cappuccino, the bill did not even have a barcode as described by their system to be able to get the free coffee. Few days later I tried again without success by scanning the barcode on their screen. Even giving them the voucher number does not work. They keep on deducting it from my linked credit card! The employees working at Mugg and Bean can not even help me and there is no help number. Useless.