If you have every record of that coin in your wallet, no need to worry. Just send a ticket to the support of that exchanger. And i heard that Bitrex not support FUN anymore, but you still can withdraw it though. Whats your problem with HITBTC ? cause you now mention it in your questions.
Sometimes it's not true. I had some INPAY on Cryptopia and they delisted it
We provided over 60 days notice on the delisting, unfortunately all wallets have already been removed from the system and no further recover is possible. Thanks Cryptopia Support