Tikona — Poor service by tikona!

I am T.S.Kishore Srivathsan residing at mogappair east, chennai. I availed for Tikona broadband connection during the month of January, 2016 and I opted for the Rs.850/- plan. Upon making the initial subscription and several calls, Tikona sent a service engineer who came for the installation of the same. His mobile number is [protected] with the True caller ID name Sasi dharan. The person who attended calls during subscription contacted me with the number [protected]. The service engineer instructed that the installation charge was Rs.750/-, but if the payment was done for 3 months in advance, the installation charge will be discounted to Rs.200/- or so. Thus, considering his suggestion, we asked the total amount to be paid and paid an amount of Rs. 2805/- online on 10-Jan-2016.
Then, on 26-feb-2016, I am getting a bill amount of Rs.471.18/- in my user ID:[protected]. When i called the customer care immediately after the receipt of bill, the person who attender me was Mr.Ajith and he said he will make a refund within 1 week. Since i did not receive any amount till date, I again called the customer care and the caller said me that i should have paid an amount of Rs.3200\- which includes the 14% tax amount and so i was not eligible for the plan.
This information was not told initially by the person who attended me during the subscription, the service engineer or the customer care person who attended me initially. This clearly says that the fault is with the Tikona officials. I am heavily frustrated by this service and so, in order to rectify this in a professional manner, kindly send me the extra tax amount that i should have paid earlier so that i can make the remaining settlement now. And kindly make me eligible for the plan. That is, till 10-Apr-2016, I should not receive any usage bills according to the plan.