Is this your first withdrawal from CEX ? Is your transaction still pending on CEX ? Or nothing showing? If the transaction isn't appearing on the block explorer, it does mean CEX didn't broadcasted the transaction yet. We are unable to help on this case and only CEX could help you. That's what the problems with centralized exchange.

Anyway you can check on web version if transaction still pending for some reason. I have never used it before, so try to contact with support or mail them. Otherwise try to contact via there social media, there is no other option.