Money Given on Credit

Hi, I was using Demat Acc.Handling service from NK Traders whose address i don't know as came to know through facebook.But third of joining their service they asked to lend 3000 Rs and promised me to return next day,as we already had 1-2 transactions for profit sharing so i trusted him without physical introduction.That day they gave me loss of 3000 Rs still i lend him money.Then after weekend he again asked me to lend 2000 Rs and i refused him that i am already shot of money due to huge loss and don;t have enough money in account.But he urged me to lend him and promised to return 5000 Rs next morning.But next day they gave loss of 11000 Rs in trading.Thinking of previous lossed i left trading service as already suffered huge loss of 3 lakh.Then next day i asked to return money but they were making excuses to return in few days and this way week passed and finally they started asking to join their service telling that 'aapko profit nikal dege'don't worry'.But i told them that i have left trading as don't have sufficient funds and please return my money as promised.They never received call earlier also ,we use to communicate through only messages still i trusted them and helped him.How people break trust for just little amount. Please suggest how can i file a fraud case to teach him a lesson.