Olx India — I'm complaining about a fraud of mobile

Address:	Kolkata, West Bengal
Website:	Olx

I sold mobile to a person who received it and yet not paid the money
Wen i told him to return the mobile to me, he stopped answering my calls n messages.
He told to give courier charges to return the mobile and wen i paid him, now he's least interested to reply.
I want some action to be taken against that person
Name of the person is shivam shukla
Address: 1st floor banarjee house, indiranagar road kanjilal para rajarhat kolkata