Vodafone India — Charging over the credit limit

Address:	Kolkata, West Bengal, 700091
Website:	www.vodafone.in

I have been using vodafone services since years, but this time its really disgusting, when i switched off my data services in india - as a process it does not get activated automatically in other country while a person use international roaming for calls, but they say it happened this time.
Then my credit limit is 3000. They now charged me a whopping amount for 1 lakh inr for the name of data connectivity.
1st of all how come customer is liable to pay such amount when he agreed for a credit limit.
In the era of high end technology - how couldn't they bar the outgoing and data services if it was going above the credit limit.
I am agreed/liable to pay the normal call charges and within the agreed credit limit. But they still remained silent on this and keep on sending reminders for payment without sending me the corrected bill, even after my communications to their central team.
Vodafone is a multinational company - i believe they believe in justification and cant put customers in a situation of harassment.
My email id [protected]@yahoo.com
Interaction number[protected].