What is the time interval of those transaction? Some exchange find it irregular activity once you deposit/withdraw simultaneously in short period of time especially you are not KYC verified even if its not hitbtc. They will surely throw you the KYC bullet if you do that on any Centralized Exchange. But if you do your transaction with long interval then Hitbtc just want to messed up o your Non-KYC verified account.
Simple solution. Complete KYC if not then forget about it. They will never release your fund. That's how shady CEX work.