Received vouchers that could not be redeemed

So I made a purchase over R2K on Friday (07 Sept 2018) and I received 14 R20 vouchers to use on the weekend , when I went to redeem those vouchers , 1 was not reedemable. We stood at the counter for more than 10 minutes (with disgruntled customers behind me ) and still 1 voucher was not working. I eventually had to pay for the exta R20 . The cashier advised that I come on the Sunday to reedem it incase there was a limit , I went on the sunday to purchase airtime with the same voucher guess what , it was still not working !

Why provide me with more than enough vouchers if you know that there's a limit and I only had 2 days to redeem that voucher , I feel ********** , even if it was only R20 but the R20 would have made a difference just as much the purchase of over R2k did to Pick n pay.

You are ripping us off the same you did with scrachcards