Hi,
If you refunded via the original transaction in PayPal and it's showing as complete, then the funds will go back to source. If the buyer funded with a debit card it will go to their bank and takes up to 7 days; credit card to their card - up to 30 days. Any other method to their PayPal balance.
It should show as 'refunded' alongside their original payment.
Obviously don't send a separate payment!
They won't be able to open a dispute if it's showing as complete.
If messages are coming through eBay, then there's a link at the botto to forward to eBay.
If you haven't done so, add to your blocked bidder list.

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