I can relate with what you must be feeling at this time but would suggest you don't allow that becloud your judgement. Tradesatoshi is one exchange site that I know that the promoters have gotten greedy or that have security issues which could have made your account vulnerable to this unfortunate situation.

I want to believe you must have reached out to the customer care because they would have been the best one to give explanation to exactly what happen as every response you get here would only be guessing without any basis. What I think is that maybe they are carrying on routine maintenance and they had to disable some of their services available end use. Again , I have seen this where some particular wallet are singlehandedly facing synchronizing issues with this your balance might not show until the issue would have been reduced. But for perfect understanding, reach out to customer care then patiently wait for their response.