Gurudev Motors — Charged for my vehicle service in spite of being in AMC

Address:

600007

My vehicle TATA Indica registration no.TN01 AA 2264 is under AMC which ends on 16.07.2017 had air-conditioning problem. I left my vehicle for service with them and was told that it will incur a charge of Rs.20, 000/- to fix the a/c. For which I denied and asked them to go ahead with regular over oiling service covered under AMC. They changed the Oil and charged me Rs.5, 610/- (Rs.3033 for oil change and Rs.2756 towards labour) This is not digestable. Why they charged such an high labour. As far as my AMC contract they said it is null and void as TATA MOTORS have printed it wrong on my contract and it is not for 3 years but for 2 years. I need your help to resolve this.