Damaged by AustPost - what to do?

Hi,

 

I've sold a set of phone screen protectors and the buyer has indicated they were severly bent by AuistPost during transit. He supplied a photo which certainly looks like the postie was bloody careless. Anyway, buyer is asking for replacements. There was no insurance, and I don't see how I should be liable for AustPost carelessness. The items were packaged appropriately, and postage was free - I'm making a very small margin on these items and can't supply replacements without losing money on the deal.

 

What should I do?

 

 

Cheers,