Wrong product.

I've order 4 X Food Vacuum Sealers from Snatchers through Bid or Buy. I've paid with my Credit Card. It was delivered but wasn't what they have advertised. I've e-mailed them 3-time for a returning address. They acknowledged receiving my mail and sent me reference numbers with the assurance that they will contact me within 48 hours, but that's where it ended. How can they refund me if I don't have a return address?