It's far too late to ask for any refund from eBay, they will fully refund an item not received if the buyer opens a case for this within 30 days of the item's last estimated date for delivery. If you opened a case recently, it would close because you are far too late.
I believe you're too late to claim from your payment provider too, you can try, most though, offer a 120 day buyer protection policy.
@mtay3566