Yobit is a scam they keep their Wallets on maintenance indefinitely and will not allow you to withdraw their old coins. I have been trying to withdraw my OMG coins without any luck for over 6 weeks now they don't respond to any of their support tickets or telegram Channel
I know it right and I don't understand why people keep on using them even there are problems that are existing. Their support aren't really helping out those traders that are in need.
FWIW, I recently transferred in some bitcoins to Yobit. Did some trades, then moved them back out of there with no problems.
You are one with the very few people that has successful trades and didn't experience any problem at all.