Havells India — Technician charing money for geyser under warranty

Address:

Khasara no - 46/3, Gali No 7, A block, Kaushik Enclave, Burari

I have got Fabia 15ltr geyser installed at my house and its been just 6 months which is still under 2 year warranty and now suddenly stopped working. I registered a complaint and after some time technician called and informed that the service is not free and i have to pay 500 for tank cleaning. Why should i pay when the geyser is still under warranty? when i bought it, the dealer shop mentioned no such thing and in-fact he said there won't be any service charges if its under warranty.
These middlemen are fooling and looting innocent consumers, Havells should take strong action against these people. or I am not sure if its with Havells consent these people are charing for extra money which they should be ashamed of.