2 years? This doesn't make sense. Did you send that amount 2 years ago or did you send partial amounts which add up to 0.4 BTC through out this duration op? Either way, this was a stupid move since there are far more legit sites out there in comparison.
Try contacting
https://bitcointalk.org/index.php?action=profile;u=116564 who handles their thread in this forum(He has not been that active lately though).
"lately"? He hasn't come online for 6 months now!

Well, judging by the OP's inability to write a more full post with details, he's either is lying for unknown reasons (he doesn't look so angry tbh!) or he's just stupid. But I would expect competing site to create newbie accounts just to FUD on other sites.
Probably happened two years ago then he just suddenly shared it today perhaps he's too tired of asking their support to return his funds or he's just making up some shit story to make a bad reputation on the site. But it doesn't makes sense too since he just said that the site was closed/closing already. I don't know what's the truth either.