You are responsible for delivering the items safely to your buyers. The buyer claims against you by opening a case through Ebay.
It is then up to you to claim from the carrier.
This is a link to the Packlink page:
https://support-ebay.packlink.com/hc/en-gb/articles/360014270619-EasyTicket
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)