Casual Chat with prostitute on whatsup

Few days back was using a friendship app so casually had chat with few accounts so few days I got a call from some guy stating as Delhi police and said me we have arrested a prostitute who has ur number in whatsup then I sId him have not ever indulged in any sex chat So he said I have screen I shot which stated you had asked for real casual meet Then I asked what issue in that he said they girl asked you for money for cam sex I said yes but after that I did not responded to the number becoz i am not involved in such kind of activities nor did i call or met So I told him I have not done any crime it's just a friendship chat and when I came to know she is a call girl I just ignoredToday again I got a call from a guy named ASI Aman singh from Delhi police He said me the same thing and threatened me to register an Fir on my mobile number and send local.police to my place and get arrested and take down to delhiThen after some time he asked me Rs25000 to not file any case Have asked him to go ahead and send me the Fir copy and said him will register against him on cyber cell Kindly advice