Edelweiss — Brokerage not returning

Sir, I deposited advance to m/s edelweiss company for trading, for low brokerage they said we will return it money i[censored] closed a/c. I applied for open demat a/c with edelweiss before 2yrs. I paid 10 thousand rs as advance brokerage to them I used only 2000 rs. From last year I talk to them to closed my a/c and return remaining brokerage 8000.00 rs. They are saying we will not policy to return remaining amount. Pls suggest how can I get my money from them. Regards Alka