Worst Customer Service and Post Sales Service

We purchased two fireplaces from Fireplace and Chimney both of which they were running a special on. One the day the 2nd Fireplace was supposed to have been delivered, I was advised that they were out of stock and was given other options to choose from. At no stage was I advised that the option chosen by myself was more expensive. My Husband received the invoice and paid for the item not realising that we had paid much more what we had originally chosen. I was under the impression that I was getting a like for like in terms of the price as I was not advised of any price difference. Upon raising this with Management for the store, they did not take any responsibility for this instead referred to this as "this was a simple misunderstanding between Janine and yourselves and was in no way a ploy to coerce you into paying for something else that you did not want." To settle this matter I was offered a R3000 refund which I accepted on the 22nd of April. Despite their promises to pay me the refund I still have not received the refund.