You’re not permitted to name and shame, as per the Community Guidelines. A moderator will be along to remove the seller username from your post.

Have you read eBay’s MBG policy page? The link is here: https://www.ebay.com.au/help/policies/ebay-money-back-guarantee-policy/ebay-money-back-guarantee-pol...

It clearly states the timeframes and T&Cs. You do realise that the MBG isn’t a product warranty? A money back guarantee is a money back guarantee - purely voluntary on eBay’s part and with clear terms and conditions. It covers you in the event of item not arriving, and item not as described upon arrival. It’s not intended for something going wrong later down the track.

For that… you need a warranty. See this post (https://community.ebay.com.au/t5/Buying/Seller-not-honouring-their-warranty/m-p/2260767#M105087) where I explain in detail why - if you need a warranty - you need to buy from a seller who is:

1) an eBay seller registered on eBay Australia 

2) an Australian business (with ABN), and

3) authorised to sell the item in Australia by the manufacturer or local distributor,

… if you’re buying on eBay.