anybody know how to akt when a customer hussel me the seller and get help from ebay

[trulpaulse_0]

a customer buy a item from me, i send tracking nr and the reciver get the item pick it or recice the paket to the door (all by the post and deliverd exatly by the clock) so the paket is DELIVERD!    5 days later hi decided that he want to try to get his money back by telling ebay he dont recive anything, ebay then decide to give him his money back even when i send tracking info the exakt date the exakt time the customer recive the paket, ebay goes in to my account and pick 160euro and pay to the customer,,,, anybody have idea how to ackt??