U-Count Rewards Mall- Data Vouchers Don't work

I bought an MTN Data voucher via the U-Count Rewards Mall and attempted to load it and it did not work, gave an error message that the service did not exist. I called the call-center to get assistance on loading it and I was given a new set of instructions to follow which did not help either. I was then directed to try and resolve this with my network & they weren't able to assist as the deal was between myself and the service provider (U-count rewards in this instance). I made several calls to the Std Bank call center to try and close the issue but no-one could assist. After 2-3 weeks of following up on the same request, with a page full of of reference numbers and no success in getting the voucher to work, I asked for a refund back into my U-count account where I was told that this could not happen as I had already received the voucher, regardless of whether it was a valid voucher or not. An e-mail was sent by the call center agent informing me that my query had been dealt with and closed from their side, not sure what that means as the voucher still does not work. I've been attempting ever since to load the voucher, with no success, in the hope that the next time may be my lucky day. Since then, I'm weary of buying anything from the On-line Mall as I take on full liability whether the item works or not.