How can ebay buyers just not pickup there package and open up a case against you?

[temp20190328h]

I always though ebay and paypal gives you protection in exchange for the fee they take. IA buyer ordered $475 worth of stuff and then just refused to go pick it up from the post office after being absent when signature delivery was required. Now he opens a case, paypal takes all my money and ebay charges me a forsale fee? 

[Whac-A-Mole]

Ebay and Paypal protect you for item not received and unauthorised transaction.

but they cannot force the buyer to pick up the package.

hopefully the package would come back to you,