No response from PNP customer care

<p>I loaded vouchers onto my PNP card, one of which was if u spend R100 or more you get R50 off. Vld till 12JUL. There were other vouchers loaded too. When I got to the till 2 of the vouchers went off. But not the R50. So i queried it with the cashier. She advised in a snotty way that the systems were off line. That couldnt be right, cause on the slip 2 vouchers showed came off & when I looked on my app, it was also gone. So how could the system be off line????? I emailed customer care on Monday & today is Friday...I havent even had a response!!! Now yesterday I got another email with the same voucher vld till 19JUL...PNP still owes me the other R50. I have made a copy of the till slip. Waiting not so patiently!!!!</p>