Airtel — arbitrary increase in rentals

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Pondicherry, Puducherry

d/s i have been using airtel landline and broadband for almost 4 years. yesterday, they have sent the following SMS ' due to rise in input cost, eff.26.03.14 rent for your broadband ID:xxxxxxxxxx will be revised from Rs.649 to Rs.749. Queries? visit www.airtel.in/dsl-faq " do the company has any right to increase the rent arbitrarily? do any of the users of this forum got such msg? what should we do to stop acts like this? yr valuable feedback is much appreciated aps