1) make post to provide proof of your account read this
https://bitcointalk.org/index.php?topic=497545.0.
2) send pm with your proof to Administrator .
3) ask trusted member to give your account red trust
4) ask global modulator to ban your account
This suggestion is enough in order to report or recover your account. Or, did you try to send a private message to the said account holder? They might bought the said account without knowing it is a hack account. Hop have a sign message about this account of yours.