Airtel — airtel sim not working and no assistance provided

Address:

East Singhbhum, Jharkhand, 831004

Airtel sim on my handset is not working since 23-03-19. Called on customer service, but no help provided. Was asked to go through app. When my sim is not working, how can i go through app. Tried sim on other handsets. Everywhere it is showing "sim error". Sent mail to [protected]@airtel.in. They asked me to call. When i wrote i am unable to call from my phone as the sim is not working, they again sent a mail to call and tell the problem.
Meanwhile i went to jamshedpur airtel office and got a new sim, after due authentication from airtel. To utter dismay, the "new" sim is also ahowing "sim error" in different handsets.. Request airtel to stop harassing consumers like me