I completed market making contracts worth $6000 USD, however HitBTC have not paid, and are not responding to emails or questions on their forum asking what has happened to the money.

They've now deleted the forum post I made too (https://forum.hitbtc.com/index.php?p=/discussion/9/hitbtc-not-paying-out-on-market-making-bonuses).

If you are considering market making for them PLEASE DONT! You won't get paid, and if they aren't paying their bills there is a good chance that they are about to shut down.

/Steve