Worthless Guarantees from AliExpress and Netac Official Store

 I purchased an NVME SSD from Netac Official Store via AliExpress.

It is offered with "75-Day Buyer Protection Money Back Guarantee":

We promise your money back if the item you received is not as described, or if your item is not delivered within the Buyer Protection period. You can get a refund 15 days after the claim process finishes. This guarantee is in addition to and does not limit your statutory rights as a consumer, as granted by all mandatory laws and regulations applicable in your country of residence.

The package was delivered via postal service.

My local post office delivered the package to the wrong address and updated status to delivered.

I contacted my local post office and they confirmed that they delivered the package to the wrong address. They attempted to recover the package and deliver it to me but were unable to do so. They deemed the package to be lost.

My local post office cannot compensate me for the loss but they are willing to pay compensation for the loss if the sender makes a claim through the origin post office.

But AliExpress and the Netac Offical Store do not accept the emails I have forwarded from my post office confirming that they lost the package and did not deliver it to me.

They deem the communications from my local post office: "The evidence from NZPOST is not so clear to show the problems, please provide more clear evidence as required so that we can tell the problems obviously"

This is what NZ Post said:

Thank you for your patience. 

Sadly, your parcel has been delivered incorrectly, despite our attempts to recover this parcel from the incorrect address we have been unsuccessful. We have deemed this parcel to be missing. 

We recommend you contact the sender and request they initiate an enquiry/claim with the postal authority of the sending country. 

Please note claims for compensation for the loss or return of an international item can only be made by the sender from the country of origin. New Zealand Post has no provision for compensation for incoming international items. 

Our sincere apologies for the inconvenience caused by this incident.

How is this not clear? They made a mistake. They admit it. They are willing to pay compensation through the normal channels for international shipping.

International shipping is fraught with human error and acts of god that cause losses. Ships sink. Shipping containers go overboard. Warehouses go up in flames. All sorts of things. 

I don't mind that there was an error.

But obtuse refusal to accept the clear acceptance of fault and liability, to obtain the compensation offered and to send a replacement or refund is offensive.

AliExpress' and Netac Official Store's guarantees are worth nothing because they are in China and the guarantees are unenforceable from New Zealand, and neither AliExpress nor Netac Official Store are willing to honour them.

Update: NZ Post has changed their story. Now they say the package was scanned "near" my address and they don't know if it was delivered to my address and stolen or delivered to some other address. They maintain that in either case the package was "delivered" so they refuse to change the status in their tracking system. Still AliExpress is at fault for the delivery failure: they sent a valuable package with no signature required. Had a signature been required, the package would not have been left where it could be stolen. I would have gone in to pick it up and sign for it.

AliExpress has my money and I have nothing. Because they were negligent in how they sent it, not requiring a signature, allowing it to go missing rather than me receiving it. But from their perspective, all they have to say is: "The evidence from NZPOST is not so clear to show the problems,please provide more clear evidence as required so that we can tell the problems obviously"

The problem is: they have my money and I have nothing. But they don't care about that.