Most of eBay's systems operate with software bots, and are unable to handle anything other than common situations. Here is the process I would follow.
1. Check with the credit or debit card system / statements to see whether or not the initial charge was actually posted to the account.
2. If it was posted, check to see if the refund was posted. The refund might be delayed somewhat, maybe even as much as 10 days.
3. If there is an initial charge but no refund, then I would make ONE attempt to contact customer service through Facebook to resolve the problem (the customer service that one would get through the links here on eBay is human-based, but they are not empowered and work according to scripts, which is not much different than a software bot).
4. If #3 fails, then I would file a claim with my credit or debit card claiming that the item was never shipped and was supposed to be refunded, but that it never happened.
