Airtel — using my email for other customers numbers

I have a registered airtel data card number with my email registered for bills. Since this is my only number i have registered with airtel. But i have been receiving emails from airtel for billing registration and billing updates of customers registered on my mail id. Several unknown numbers are registered on mail id and still counting. Each day a new number is registered on my email id. I have complained to [protected]@in. Airtel.com regarding the issue. Next day their person calls and says they will sort my issue but it seems they are doing nothing about it. After sending a few emails towards [protected]@in. Airtel.com one representative asked to mail it to their nadal officer. I got a reply but still i am facing the issue. I hope airtel could provide a better service by not making others email or other details public to everyone else in such a manner. By doing so they are compromising others data to third person. I dont know what else to do since i am tired of sending emails after emails with no positive change. I am attaching photos of a few numbers that are registered with my email id. Hope this brings a positive change.