[Resolved]  Idea Cellular — network busy issue

I have been facing a lot of trouble while placing calls on my idea mobile over the past few months. There are frequent call drops, disturbances in the line and network issues. At times, i am not able to make or receive any calls at all and a message is displayed, saying 'network busy'.
Even restarting my mobile and inserting the sim in other mobiles has no effect on this problem - which is indicative of the problem being solely with the sim or idea network.