Vodafone India — waiving of my bill

My Vodafone mobile no. [protected] has talk plan of 249 and internet plan of 250 .When I exhausted my 1 GB internet plan they activated my unlimited internet plan without any prior notice and when my 1 GB plan was exhausted I call to the customer to activate new internet plan of 500 MB which is of 150 Rs. at that time they did not inform me about this and they simply activated my plan. I have tride many times the customer care no. but they cut the phone in half enquiry . so i need an answer and want to waive off my bill...