Airtel — my airtel number is allocated to someone else

Address:

Bangalore, Karnataka

I have taken airtel mobile number in June 2013 at Kengeri, Bangalore location. This number is linked to all my bank accounts, social websites and every where. In Feb 2018 I moved to United States for short period and from June 2018 my number stopped working. I came to know that my number is allocated to someone else without my notice. Now i'm not able to do anything. My apple id is linked to this number so I can not even communicate to anyone. All my bank details are going to Mr.Sudhakar Reddy. I'm in a horrible situation. I tried even calling airtel customer care and their response is worst ever expected.
I need my number back.