If you haven’t received your items within the EDD (estimated delivery date - which is a range from dd/mm/yy to dd/mm/yy), you need to act within 30 days of the latest EDD (that latest date by which it’s estimated by eBay that it should have arrived),

You can open a claim once the EDD has passed, but no later than 30 days later than the latest EDD.

https://www.ebay.com.au/help/policies/ebay-money-back-guarantee-policy/ebay-money-back-guarantee-pol...

If it’s been longer than 30 days, post here again and we can suggest some other ways to be refunded.