1) do you have any letter from you broadband mentioning internet broad band speed .
2) did you give reasons for termination of connection in 2012 .did you mention broadband speed is very slow and contrary to assurances ?
3)when you shifted to monthly payments of rs 3000 did you receive bills mentioning arrears due and payable?
4)you must reply to legal notice deny your liability to pay Rs 6258 as broadband speed was slow and contrary to written assurances
5)amicable settlement is best solution as litigation costs would far be more than amount claimed by you broadband