Clicks Store does not accepting their OWN voucher (sounds like a joke but its not)

Hi Clicks I visited Clicks The Berg, Bergbron, JHB on Saturday, 10th June and was absolutely disgusted at the service I received. They blantantly refused to accept my Clicks digital voucher as form of payment. This store advised me that they previously tried processing a digital voucher once before and they had issues balancing the till afterwards and therefore do not process vouchers, they had to pay out of pocket for that transaction. They seem have decided based on their own judgement that they are special and are autorised to be excluded from accepting any digital vouchers. What utter nonsense is this! The lady at the till, I believe a supervisor, she was a apparently filling in for the manager, refused to give me her name, she says she is the one who has issues once before with processing vouchers. She tried calling Vuyo and Siphamandla (they apparently don't know their surnames), some other area managers, who were unavailable but apparently would also refuse accepting the digital voucher due to the 1 past issue in this particular store. In the past, perhaps the system was down or something, but they now want ALL customers to pay and suffer for one mishap. Their customer service is simply atrocious and all the staff at this store need to be dealth with severely. The only person who was willing to give me their name at the store is Kundai Mukwamiri. This store is the closest to my home and most convenient but sadly I was refused any assistances and was told to visit another clicks store. I then visited the Clicks branch at Clearwater Mall and was serviced with a smile. I must advise also that they had adverts displaying on screens at the tillpoints encouraging customers to purchase Clicks Virtual Vouchers. Why do this then if certain stores are excluded from accepting vouchers? As per your website, "Where can mobile vouchers be redeemed? Vouchers can be redeemed for goods (excluding airtime & cellular phones) at Clicks Stores stores nationwide in South Africa". By the way I won this voucher in a competition and will start advising big brands and companies not to issue any Clicks vouchers as prizes in future as this Clicks branch refuses to accept their own voucher! How absurd! I even advised this store that I reside 5 mins down the street and would be happy to leave my details should any issue arise with payment but they simply refused to assist me the customer. They need to be reminded that the Customer is King and the Customer is always right. The whole store, Clicks The Berg, Bergbron, JHB should be sent back for Customer training, sies man!