Frustratingly ripped off by discogs

I sell records on discogs. I’m a guy, not a store. Mostly I just recover money from extras, doubles, upgrades, etc.

I sold a copy of a record and shipped it. The guy claimed I never shipped the record, even though he had the plastic, the box, and the sticky with my handwriting on it. (I saw a picture). I have never seen a more obvious theft, especially considering he changed his story multiple times.

He put in a claim with PayPal, and they took my money.

I doubt I have recourse, but it’s so frustrating I can’t put it in words. I don’t know what to do.

Edit/update:

I wanna post an update later when I have a little more time. This actually escalated this morning, but based on most of your responses, I want to post up here that I did send with tracking, and you are right: I was ripped off by a Discogs user, not Discogs, but PayPal is the real problem. Follow-up later.