nomorerack.com Refused to refund money Internet

I bought sheets from nomorerack.com, and they were torn when I received them. I emailed the company, and they told me that I had to pay to ship them back. When I pushed, they agreed only to give me store credit for the shipping costs. I pushed further, and an employee finally agreed to refund my money for the shipping costs. Now, however, the company is refusing to honor that promise. They are still only willing to give me store credit. I don't want store credit with them. They have terrible quality merchandise, and their cusotmer service is the worst I've ever seen. I have no intention of ever shopping there again. If needed, I will sue them for breach of email contract to get my money back. This has been a terrible and time-consuming experience. Do not buy from them EVER. You will regret it.