Ideally, they should refund it, but because you're also at fault here I doubt they will cooperate that much (it's Yobit we're talking about here). How much you've deposited here? If it's not that much, maybe letting it go is a better option. Use your time wisely, Yobit is famous for its lack of support for some users.
I was making a large deposit in parts, the one that wasn't credited was 18 ETH, unfortunately. If it was a small amount, I would have moved on.
Thanks for the comments, everyone. It's been 2 weeks now, and I'm in contact with them on and off. I can say that at least they are communicating, but progress is very slow. There's some hope they'll refund, but not counting on anything. Lesson learned - I'll stick to the established, customer friendly crypto exchanges. I don't mind much, because this is the first time in 5 years of crypto trading I've lost any tokens, and I'm motivated to make it the last.
By the way, they absolutely should refund. Legally, you are obliged to refund payments if you are unable to tender services. It's not like the ETH is lost. It was clearly diverted to their ETH wallet, and they clearly have access to it. I'm more than happy to pay a fee / fine of course because I fully accept it was my fault. Sadly, with these overseas crypto exchanges, legal recourse is basically out of the question. If anyone has any suggestions otherwise, I'd greatly appreciate it.
If that's the last resort that you can do, better to give them or allow them to take the fees from you, but they are obliged to bring your money back,
as what I understand you successfully send your ETH to their wallet and there's no issue about it, so refunding should not be an issue but delaying
tactics I guess, keep trying as it is yobit obligation to pay you back.