Not really i mean what are you going to do if you did catch up with him? The Bitcoin is probably already spent
Just take it as a lesson learned you should have no need to pay upfront for a service anyway and you could have used a reputable escrow which would have covered you and him if he never wanted to use escrow you would have know early on.
Mind me asking what kind of advertising the $400 was for?
Maybe you should move this to scam accusations or just wait and a mod will probably move it to the right place.