Kent R O Systems Limited. - Unfair Trade practice Promised service is not provided

We bought a KENT RO purifier in August ****.
We took * years AMC for KENT RO after paying Rs.***** in Feb ****.
Some of the things that are included in AMC are:
* service follow-ups every year
New water filters every year

Even after buying AMC, no technician came for checking and servicing RO from Feb-** till April ****, i.e. for ** months, no service was done and no filters were changed.

We started observing some changes in water pressure in KENT RO and some change of taste in water so we raised the complaint. The technician told us that the water storage tank has gone bad and we would need to buy a new water tank for Rs.**** as that is NOT covered under the AMC. This was news to us. No where in the agreement it’s mentioned that it's not covered.

We have following grievances
Even after taking AMC for * years, no technician came to service and checked the water filter for ** months. It is clearly a case of “Unfair Trade practice - Promised service is not provided”
Water filters were not changed for more than one year, causing potential damage to our health.
They are saying that the water tank has gone bad, there is a strong possibility that it has gone bad because they didn’t do timely service / cleaning.

In earlier occasions, when we didn’t have AMC for one year, KENT RO technician used to call and come frequently for service because the service was paid at that time and on every visit they used to change some part of the system, In a span of one year, they changed almost all parts of the machine.
After taking the AMC they haven’t even serviced for ** months, forget about changing parts as needed.

This company is cheating people on a daily basis. It looks like taking AMC is only an insurance that they don’t dupe us on a periodic basis. They really don’t care about the machine.

Please look into the matter and take some good measures.