Airtel — Airtel My airtel mobile number in someone else name

My airtel number: [protected]
Contact me : [protected]
I am using the airtel number for almost 7 year now. Today my mobile was lost and i went for a duplicate sim and then the airtel shop people said that my number is in some one else's name? How is this possible? If i dont get back this number my business will be in huge loss.

I need to recover this number immediately. There should be some method that i can claim my name. If needed i can submit my bank statements where this number is used for google pay/phone pay etc..

Regards
Ashok