You went to a gold shop and found out they were cheating the customers by not selling hallmark gold. You will
1
Leave the shop and tell your contacts not to go to that shop
2
Inform the customers at the store about the cheating and ask them to register a complaint with the police.
3
Call the police and go on your work
4
Question them, call the police and register a complaint along with other customers with the required proofs.