Airtel — Identity theft for new sim purchase

Hi
I got a call from TRAI representative saying that a sim card bought on my name with number [protected] has been misused in maharshtra for spam and there has been a FIR filed in my name. I explicitly state that I only have one active number [protected] and I am not aware of the other number. I also do not have any information of the FIR until TRAI call.
Even if my aadhar was mis used why was the sim issued without checking the person buying and aadhar given and without checking biometric which is not my responsibility and is responsibility of the seller.
This is responsibility of TRAI or the aircom provider legally and I am a victim here.
Without any investigation TRAI harassing me by threatening to discontinue my active number in karnataka and creating mental harassment.
I need this resolved immediately