If you had done some findings about Hitbtc before depositing your money there, you should have probably realized that they are a very shady exchange, I traded on Hitbtc for about two years before deciding not to ever trade there again, and even up until now, I still have parts of my funds stuck there that I've not been able to withdraw, I just simply left it for them.

If you have the financial ability, and also depending on the amount of  your money they how holding, I think what you should do is report them to the authorities in a country where they have a legal license to operate, this is not a guarantee that you would get your money back, but then, I think it's worth a try.