Terrible customer service, lying and no integrity at Total sports Greenstone

So i go to total sports greenstone, pick up a shoe i like, marked at R599 and it was reject. So i left it, a few days later i decided that the damage was really small and i could sort it out and when to pick it up and it was marked R899. They said it was a mistake on their part. Firstly they said they can't sell a reject shoe and will pull it from the shelves but when i went back it was still there, so blatant lies on their part number 1, which is terrible customer service and number 2, it's obvious if a price was given to you you expect to pay that price, even if it was a "mistake" on their part, if they don't do that they at least give you a voucher for the amount that was told to you. I mean most if not all other major stores do this, including airlines. Why the terrible customer service and the blatant lying. Total sports was always a store i could trust, but now I think they really don't know how to get honest staff, and don't have good company policies. It's honestly shameless and distasteful.