They are just extremely slow, I sent them 1 single verification document for my ''proof of residence'' and still nothing after almost 1 month. I'm not going to use their services anymore because I can't spend months to withdraw money, I don't think they are a scam though but still really annoying to wait so damn long. Really unprofessional exchange right now.
Don't ever say that mate that this trading site at cex wasn't professional, it just happened that blockchain congested during those days that you've doing trades. It also happened to me 3 weeks ago, encountered long time processinng upon the withdrawal of my bitcoin for exchanges of btc to fiat trading sites in my local country of residence. It took for me 24 hours of waiting, but eventually the funds returned to my exchange wallet, and I repeated the withdrawal process and did it successfully. My advice for you is always be patient on what you do, because there's a possible solutions of every circumstances.