When I try to withdraw USD it says "Can't perform operation. Please try again later.", and when I try to withdraw cryptocurrency it says "You cannot perform this withdrawal for security reasons, please contact support for assistance.". But when I log on the site, there is no reminder, nor any official announcement to traders.

Currently I'm deeply worried about the situation as I have more than 6 BTCs and 6K+ USD and some other cryptocurrencies in my CoinMKT account. I have sent several emails to support but no reply at all. I don't know how I can do. Can anyone give me some help? Thanks in advance.

Thanks the answers from mayax and quone17.

I was still able to withdraw last week, but from this Monday I cannot withdraw. What's more, there is no formal message or reminder at all when I log on the site, and I still haven't got any feedback from the support. That's why I am deeply worried. At least I don't believe this is any style of professional operation.   

I will follow up the withdrawal issue every day and provide update here.

I can trade or deposit without any problem. But when I try to withdraw USD it says "Can't perform operation. Please try again later.", and when I try to withdraw cryptocurrency it says "You cannot perform this withdrawal for security reasons, please contact support for assistance.".

Currently I'm very nervous as I have more than 6 BTCs and 6K+ USD and some other cryptocurrencies in my CoinMKT account. I have sent several emails to support but no reply at all. I don't know how I can do. Can anyone give me some help? Thanks in advance.