Changing your password probably prompted them to kill your current session(s).
Did you look at your trade history? These are extremely thin markets on Bitfinex. A hacker probably compromised your (and other) accounts, then used the accounts to buy UTNP and AION so he could sell at very high prices and then withdraw. This is a common hacking method these days, particularly through API keys.
There's no volume for these tokens on Bitfinex. To sell AION without slippage, you may need to send them to Binance. UTNP looks pretty dead. Ethfinex does ~ 1/3 of its volume.