YoBit has been in maintenance for months (almost a year) now because they are a terrible exchange. The PIVX team bugged them about it for a long time last year, but they may have given up since YoBit hasn't responded to any communication (you could ask on Discord for the latest updates). Your best option is to sell to BTC and transfer to an exchange that isn't complete shit (Binance and Cryptopia don't ask for verification if you want a 'traditional' exchange; flyp.me is also a good option).

https://forum.pivx.org/t/pivx-on-frozen-on-yobit/2862/2