Did you close it through your ebay Plus page within the specified period to qualify for a refund ?
If you didn't then eBay is not required to refund you. If you go to the link below and scroll to the bottom you can contact eBay for help with it.
Note. We are not eBay staff here, just members like yourself, so we can't refund you anything.
https://www.ebay.com.au/help/buying/buying-ebay-plus/buying-ebay-plus?id=4755
