How can I save a person from getting extorted by a broker?

Hi This is  actually my friend is in problem, Its the first time he plans to sex with a girl so he contacted to a broker. He chat with the broker and he ask to pay the money first by paytm or bank so he paid 1500rs and he gives the number named swetha and after that he contacted her but she couldnt lift the phone he contact only through whatsapp, and my friend aksed him in whatsapp to come and pickup me (broker says he arranged the house for that) but at time came she will not come and she says in whatsapp i have a problem can u arrange 2000rs and when i came near to u i will give your money, but my friend didnt give the money and she says im suffering with the girls problem so plz arrange and i will give it to you and he didnt give the money even at that time my friend call them but she didnt lift the phone he contacted only in whatsapp.after next day broker she arrested by police so he aksed about your chat.brokr said i will manage but he ask d money 25k if u pay u will be free