If it's anything to do with  seller K who last left you feedback, if you haven't received your item by the last expected delivery date,  open a claim  immediately through eBay's Money Back Guarantee

https://pages.ebay.com.au/ebay-money-back-guarantee/

eBay Help is at the top of every page

How long have you given the seller to reply?

How do you know the issue is caused by the seller/seller's end?

Are you trying to buy something from within Australia, or from overseas?

Are you trying to buy something that is restricted?

Are you trying to buy something very expensive?

Are you trying to buy something that comes up as out of stock?

Are you trying to buy something from a seller with a banner on their page saying they are away?

Is that all the message on the page says?