Lost faith from airtel. Review on Airtel Mobile Operator

I am an airtel customer for more than 12 years now but its unfortunate that they don't trust even their oldest customers. Here is my experience with airtel.I went to Delhi during Jan 2014 so I activated roaming pack for 75 rs month so I used it for a month and called up customer care to deactivate it by month end or during first week of Feb 2014 because I had returned back to Bangalore.

But  they did not update my request and as a result I have been charged for 75 rs a month for last one year.There is partly my fault as well because I trusted airtel so much that I didn't bother to check my bill. But my last bill suddenly increased and when I checked my bill to my surprise I found that 75 rs is charged through out the year now when I call the customer care they say that they can't do anything and deny to the fact that I have given the request to deactivate the roaming pack so even without using a feature I have to pay for it.

Pathetic billing.guys please think twice before going for airtel postpaid.you will have pay more unnecessary.

Soon I will get out of this ignorant service provider who cannot value their oldest customer's.