what kind of disput do i file if a seller has over-charged me for a purchase?

[xapril07x]

on iOffer.com, a seller charged me twice for one item ($12.99 two times). they sent me an invoice and i payed. then they sent me a second invoice, and thinking it was a confirmation invoice, i accidentally payed again. in my PayPal transaction records, $12.99 is listed twice from this same seller and item on two different days (Dec. 13 & Dec. 14). i have tried contacting this seller many times about the issue but they have not responded. i want my money back. please help. what do i need to do? or what kind of claim / dispute do i file?

[BigKahuna97]

My best advice would be to open a dispute against on one transaction then upgrade it to a claim.  Allow the seller a day to input the tracking information then do the same to the other purchase.  Since the seller will only be able to input the tracking information once, you will be awarded one PP claim which would be your overpayment.

Hope this helps.