Frozen to table in under 5 min

We got to spur at riverside mall, Nelspruit, to get a milkshake. I first asked at the front desk regarding the amount available on my Spur family card to which the person working at the front desk stated that there was R100 on the card and said that the R100 could be used. I repeated the question asking again if she was sure that I could use the full amount and she said yes. Upon receiving the bill after the re-heated/pre-heated chips from the morning left overs, I told the waiter that I would be paying with my Spur card with the bill totaling to R80.70 and the card having R100 available. The waiter then slowly backed away very confused clearly not knowing the steps that followed, after a few minutes the waiter returned with the bill not doing as I stated that I will be paying the bill with the card, he only subtracted R50 which made the bill totaling to R30.70. I then stated that I wanted to pay the whole bill via the Spur family card to which he responded that it would not be possible and went to get the branch manager. The manager then explained that the card can only be used to pay in intervals of R50, I then referred to the card and asked where it states it as the card has been used previously to pay full bills that were not in R50 intervals. I then had to inform the manager on how to train his employees on informing the customer on how the card works. The manager then said that we can add an item totaling to R100 and suggested that we add an overly priced 330ml can of coke for R19.90 totaling to R100.60 and said that he would pay the R0.60 that was over R100. Long story short, Spur please get your staff up to date and educated on the terms upon using the Spur family card.