Airtel — airtel data is not working

Address:	737102
Website:	Airtel data

My Airtel number [protected] is not working properly in my area i.e in Deorali Gangtok Sikkim but where as before my 3G net use to work very well but it's been months that my 3G don't work properly it get switched to "E" and I have complaint this thing to Airtel office as well but no change