Waste of my time

I had received a R600 voucher to use at Exact. Went to the one at Mall of Africa wanting to use it. Got there a guy assisted and said the voucher was redeemed. A lady stepped in and said the same thing. Head Office was called and they said the voucher was redeemed but only R329 was used. But at the shop they couldn't see the transaction. I left the shop with my problem not resolved. Went back today and still nothing was resolved. R329 spent but I didn't get any clothes nothing. So what now?