This is sadly a very common scam on the steemit.chat, since it does not require any form of identification if you create a new user there. This problem will be around until they implement Steemconnect there (I asked the owner, but don't get any answer why they haven't done it).

Anyway, I'm sorry to hear that it is happening to you as well.. Sadly the best thing you can do is to report it to the moderators, and keep your followers informed so they don't get scammed.