Wrong 3G plan activated, & charged the customer.

I have raised the complains to airtel 121, more than six times. Sending Emails, speaking to different representatives, contacting airtel nodal sharing the emails in cc. but no reponse.

I contacted the customer support on 4th Aug 2015, to add a 3G pack for 300MB costing Rs.100/- INR into my postpaid plan. That , activated 3G for 1GB costing Rs.300/-. The very next day it came to my notice. I contacted airtel no. of times, but they said, It will charged to you now, on a flat basis, even if you deactivate the 3G service you will be charged for that. I asked them to transfer to manager/supervisor, but they always and always say he is busy and assured and promised me litterally, I will be getting a call back this day only, anyhow.. and finally its been 2 days, the promise was broken.

I am about to go no where and I have been forcibily charged by airtel, because of their mistake.