Indus Towers — tower installation issue

Address:

Mumbai City, Maharashtra

A person named harmesh lal who claims to be an employee of indus towers, mumbai asked us for money to install the jio tower at our land.
As per the registration form, it says we are supposed to pay 14, 300 as the registration fee. However, he asked for more money 5, 000 saying that our payment was late. After giving 5, 000 he is asking for 6, 000 more and threatening us that if we don't pay 6, 000 more, he won't install the tower and also will not return our money (14, 300+5000).

His number is switched off. He took the money on 13th march 2019.