Indian Oil Corporation [IOC] — Manipulating the oil filling process

I am writing to complain regarding an incident that took place recently. I wish to inform you that while travelling from Delhi, I paid for filling petrol at the Pilkhuwa Oil Company.
I asked the person in charge to fill the tank fully, what he did was he filled the tank half and making the machine jump by stopping and starting the flow of oil constantly so as to overcharge by somehow manipulating the process of filling oil.
On asking him as to why he was doing the same he revolted, but thereafter when he understood he had been caught, he filled the tank full.
As a concerned customer, I write this to inform you that it is possible that the same fraudulent practice might be happening with various other customers as well, be it unknowingly, that is being carried on there.
I request to kindly look into the said matter so that other customers of your esteemed company might not suffer.
Hope you would take the necessary action in order to discourage such practices in future.