Airtel — calls get disconnected eventually.

Address:

110084

I am user on airtel network from previous 8 years. From 4-5 days, i am facing a problem of disconnected call almost everytime. Why it so happen?
The problem has increased to such a level that neither incoming call is possible nor outgoing call is possible.
Please try to solve these types of problem due to which i am struggling to have a single call with my contacts.