In case this helps anyone: Sistemkoin is a scam exchange.

They:
- list dodgy ponzi coins for pay
- they arbitrarily block accounts (conveniently when you try and withdraw ETH or BTC)
- they leak personal documents
- they lose personal documents (ohhhh you'll need to verify your account again)
- they have major, easily exploitable security bugs in their system
- they work with ponzi operators to fake and inflate trade volumes and pricing
- they block users who try and sell dodgy ponzi coins (because of course that would crash the price).

So yeah, Sistemkoin is a scam exchange.