Airtel Chennai - I am not satisfied with Airtel mobile services..

Yesterday(25th Dec 2011), i have activated 5 Rupees Internet Pack in my mobile. I had 50 MB internet usage. During afternoon my mobile balance was Rs84. After browsing for a while my balance dropped down to Rs.0.05. I didn't cross the usage limit & didn't open any extra sites or anyting and also my usage was still 27 MB left at that time. I filed this as a complaint in Customer Care. They gave me a reference number too. They told that this will be resolved within 2 days.

The same thing happened again the same day in the evening also. they took another 78 Rs from my account. Today i have again recharged & had 43.14 rupees. Now its getting decreased gradually.. I don't know what to do..

I tried to cal 121 or 198 or 9840012345 or 9840198401, but i couldn't speak with the person there. They are telling that they will transfer this call to their senoir authority but in the middle itself they are disconnecting it.. I lost my patience in trying to this customer care anymore.. My balance is getting reduced fastly now. I need this issue to be fixed soon.. Plz help me out ASAP..