Blocked bank account due to Edgars storemanager

On 14 Dec I went to Edgars and wanted to buy 3 locket chains with earing sets at R 399.00. I told them to put it through my credit card budget account. The transaction failed repeatedly. I asked them if they chose the budget option. It did not go through. On 15 Dec I received a call to say that my credit card had been blocked due to suspected *****. At the FNB branch they told me that all the transactions was put through incorrectly by Edgars and my account was blocked for that reason. I went back to Edgars and wanted to purchase the items as the previous day. The chain sets prices were marked at R 899.00. I told them I want the items at the prices from the previous day as my transaction was blocked due to the mistakes they made. They refused to do that. I feel it is tot fare as they were the reason my account had been blocked and for that reason the items must be sold to me at the lower price.