Game Beat the Price

Good day. I went to Game Shelly Beach today and had a price for them to beat from a store in the very same mall. When I showed the manager from Game the price in writing from the other store, signed and stamped, they refused to beat the price, saying that that price from that other store was an online clearance price, which they won't beat.

Then I explained to them that their online terms and conditions say they won't beat online clearance prices but this wasn't an online clearance price, this was an in store price, with more stock available at another branch. They still refused. It felt as if I had to explain to manager after manager that I wasn't breaking any of their terms and conditions but I couldn't get through and was told to take it up with head office. Hence this post. Their manager also refused to provide a signed reason in writing as to why they won't give me the discount. Regards