Wrongdoing in oil filling at Indian Oil petrol pump.

I was at mundhwa Indian Oil petrol pump. I had asked for a refill of ₹1000. But, the refill was done only for 800. When I insisted on bill. He told he will refill for another 300. Which he did.

Details of petrol pump:
Imperial Petroleum
Sr. No. 60/40, Mundhwa Ghorpadi Road, Mundhwa,
Pune 411038
Manager:Sambhaji bhosale.