Poor customer service in a high level

I was humiliated when I went to pick n pay centre walk in Pretoria where I I was going to load a gift voucher that I received as an avbob customer rewards,I was given a run around infront of clients as if I had to beg the lady called ausnart where she had to tell me that her money will be shot on her till point as if pick n pay never a gift voucher.the service was very poor and I wouldn't recommend one of my family or friends to buy in that store.