cancelling ebay

popadom

how do i cancel a transaction from ebay-the item has been paid for but i dont want to sent.dont mind if i loose fees

and how do i block certain bidders?

hermum

Here's how to block http://pages.ebay.co.uk/help/sell/manage_bidders_ov.html#block
You can send a request to cancel but in your case I can't see that the buyer will accept, so I guess all that you can do is refuse to sell. When they raise a NPS, maybe ebay will look at the message you received however it doesn't seem as though they are interested, phoning may have achieved a better result as they tend to give stock answers.
You should open a new account to sell from to prevent this type of thing happening again.