Poor customer service

I was helped by a guy called mankala mashao who gave me a very poor customer service. I told him I am redeeming points from my thank you card. I was amazed by the balance which I was supposed to pay then I asked him if he had redeemed the points he said the card doesn't allow him bt he never informed me about that. And when I checked my receipt he only redeemed 1000 points. How does that happen when he said access was denied. I will never ever shop at this store.