Airtel — unsolicited sms from airtel for changing the network provider

I have received sms from at-airfta informing "your request for porting the xxxxxxxxxx to airtel has been received"

I never made a request to change over from the present operator to airtel. Then how did this happen? Who gave my number to them? Under what basis the airtel has sent such unsolicited message? Please take necessary steps and action against airtel. Thank you.

Please be informed that i am very happy with my present mobile service and have not put any request for porting to airtel at all.
Please look into this urgently and take corrective action against these fraudulent operators.
Else i will have to lodge complaint against airtel with my local police station and department of telecommunication which may please be noted.
Your immediate action will be highly appreciated.