HitBtc exchange lately do have some issues regarding withdraws even on deposits too which I don't know if those issues being claimed by some users on their main thread have been resolved or not. If it doesn't then t would really be not safe to use the exchange. Regarding on my experience on the site I don't encounter any problems when it comes to withdrawals of deposits and on OP situation the thing you can do now is to send support ticket and would wait until they would respond regarding on their case.