Unauthorized use of buyer account – Transaction(s) cancelled

[scifiwriter99]

I received this message from eBay: 

"We’re writing to let you know that we had to cancel the following transaction(s) because the item(s) were purchased without the account owner's permission. If you already sent the item(s) and they haven’t been delivered yet, please contact your shipping carrier to find out if you can stop the shipment."

"We have credited any associated fees to your account."

Does this mean the payment was refunded to the buyer?   

Sounds like they refunded money from my account and refunded seller fees. It's not my fault the buyer  

was allowed to buy the item. Why am I responsible for the payment?