You honestly got lucky. So many people have more than enough ample evidence to prove they provided a service or item and they still give the buyer their money back. They usually don't even look into cases. All a buyer has to do is open up a dispute with a note like "item damaged" or "no tracking" even if there was no physical product to ship. PayPal's fucking horrendous when it comes to dispute resolutions.

The only thing you can do is contact their support but they won't help you. They'll tell you that decisions are final. I don't know where you're from but every time I call them, I get someone in New Delhi who could care less. Their email support literally copies and pastes things from the FAQ. Their Twitter is the fastest way to get a response but it's less than useless. They'll give you a generic copy/pasted scripted response.

I don't know what to tell you. Their support is atrocious. Google "PayPal reviews" and just look at the thousands of 1 star reviews they have.