onevahan com - money paid to onevahan They are not returning document and money

I took service from onevahan for my car NOC . Initially they quoted **k and assured me that work will be done in * week time. Once I paid and gave document, when I enquired about the progress of work after * week they are saying my file is missing and asking me to pay *k more. When I am asking to return my document and money they are refusing to do so and behaving rude and threatening . After taking money they are talking like goons . Beware of them . Think **** times before taking service from them. I am totally stuck . Dont know how to deal with it.