Air india - CANCELLATION ISSUES

I had booked a ticket from air India to travel from Patna to Visakhapatnam. Since there are no direct flights I had to book a ticket via Delhi. Now due to some personal issues I had to reschedule my flight from ** September to ** November and now due to some reason I have to cancel the flight.
The initial cost of the ticket was **** and then rescheduling cost me another **** Rupees.
Now, first of all they have not given the option to cancel the flight online so I had to call the airline's helpline number to get the ticket cancelled. I had called them around **:** am then they said that the cancellation charge would be charged separately for * connecting flights. (PAT-DEL) and (DEL-VIZAG) amounting to **** (****+****) which would end up in me having a refund of only around * thousand. So I disconnected the call and told them that I'd confirm after discussing with my family. Then I called again at *:** PM and now they are telling me that the ticket cannot be cancelled itself. Why? Because it was rescheduled, you cannot cancel the ticket. It does not make any sense to me.
My first concern is why would should **** be deducted when I specially booked for one trip (from PATNA to VIZAG).
Secondly, why can't my ticket be cancelled if it has been rescheduled. It does not make any sense. I am losing **k in the whole deal. It just does not seem fair!!!
Moreover they don't have a grievance officer to whom I can complain. It's a messed up system.
I don't remember the Guy's name who I had talked with in the morning but the lady's name who connected with me when I called the helpline at *:** PM was Anushka.

Kindly help me out.