Tata Photon+ — They don't want to close out my account

Address:

Ghaziabad, Uttar Pradesh

Hi,
I bought a Tata Photon+ by paying the advanced 2 months pack. With this I got the device and 2 month rental at 1590/-. But after using it for a day and two found out that I was only getting 80kbps whereas I was told that it can give max up to 3.1Mbps. I called the customer care and they lodged a complaint. I had to wait for a month for the engineer to contact me. He said the there are some issues in the Vasundhara region and nearby and nothing can be done. I called again to the customer care and they said to give them another chance and lodged another complaint. This time they were quick. They contacted me in a week. But the engineer said the same thing as the previous one that nothing can be done.
I called again and requested to close out my account. They first hesitated and then requested me to transfer the device to someone I know. When I refused they said that the account cannot be closed as it came with a plan and cannot be cancelled before 6 months. They said they cannot do anything but to send another enginner.If they close the account then I will have to pay Rs.2500 approx. Its been more than a month now that I have used the device but they keep on sending the bill.

Kindly assist as I dont want to pay for something which I am not using.
Account number:[protected]

Thank You
Tuhin Kanjilal