ebay seller dispatched an item AFTER i opened a case for a refund?

[Viki]

I bought a top on ebay, i paid straight away. The seller took the money (the money transfer was "completed" on paypal so i knew they accepted the money). However the seller never dispatched the item! So a few days ago i opened up a case for a return, and just now, ebay tells me the seller has finally dispatched the item! I don't even want the top anymore i want my money back! What can i do?
the p&p cost more than the top itself, so i dont think returning i would be worth it

[Who]

If it was a business seller you tell them you want to return the goods as is your right under the distance selling regs

If they arent then there is nothing you can do unles they agree you can return them (there is no harm in asking)

[Gary Crant]

As "who"says. part from that if there's nothing wrong with the item they're not obliged.