Vodafone India — issue with billing..

Address:

old bowenpally, 500009

This is in regards to the billing issue.. It's been more than 4 years i am using the postpaid connection. Never i had any issues with the bill payment or the network. I was happy and referred many of my colleagues to vodafone..
I see that you guys have changed the plan without informing me. I was happy with 199 plan and you guys changed it to 249. How do you expect me to make the payment without my permission for the plan change.
When i called customer care they say they sent me messages, if you see the handset that i'm using it is basic handset meant only for calls... I don't use any of your 4g services..
This is totally unacceptable. I need the plan to be changed to 199 which i was using from the last 4 years or i'll port my number to airtel.. Also i need to waive off the late payment charges to make the payment if you want me to continue with vodafone. I'm not gonna pay for something which i was not informed.. Please fix the issue asap..
Appreciate your quick response..
Regards
Shabbir