paid twice

i recently bought an item, after winning i paid via paypal straight away after i bought the item, the seller then sent me an invoice a day later i emailed him stating that i had already paid and had a receipt from paypal sorting out the invoive and other bits i accidently paid for the item again, i have emailed the seller explaining my mistake but have had no reply, what would be the best course of action and is there anyway i could cancel the second transaction?? Many Thanks

---

Orignal From: paid twice