Presuming that you're signed up for managed payments, as you've only recently started selling again, eBay will see you as a new seller and your funds will be on hold

https://www.ebay.com.au/help/selling/getting-paid/getting-paid-items-youve-sold/payments-hold?id=481...

You could try going to eBay Help  at the top of the page and mentioning that the buyer has left you feedback, but  it's not always successful