Maruti Suzuki India — Forced to purchase insurance from dealer

Address:

Ambala, Haryana, 134003

I am looking for alto k10 automatic variant for this i approached the local dealer for inquiry. Everything was smoothly finalized and deal was supposed to be done but at the end the salesperson started compelling us to purchase the insurance from the dealer itself.
The policy they are offering for 18000 is available in market for[protected] rupees when i objected to this the salesperson told me that it was a Marti Suzuki India's policy that the insurance needs to be bought from the dealer itself.
This is a clear case of cheating the customer who doesn't have much awareness about this.