Changed the broadband plan without prior notice

Hi,

I am using Spectranet broadband connection bearing account no. 0051-0991-​DELH-01785​6 since Jan 2014. I had subscribed to plan Plan8GBCFRE_F (Max Usage Data 8GB). Montly Rental for this plan is Rs. 699.00. Total bill was Rs. 785.
Now without any prior notice company has changed my plan to Spectranet Advantage Monthly Subscription 16GB. Customer care is saying that there is no plan for 8GB now and we have plans only for 16GB. My monthly usage is max 7GB. Also spectranet takes the monthly payment in advance. Now they are asking for payment of Rs. 897 (monthly Rental 799.)

I have not received any prior notice informing about the changing plan.

Thanks & Regards,
Nidhi
+919818750065