Today I am getting fake calls from a number +91-7260976974 and the person on phone call pretending to be an Airtel customer care executive and asking me to update/link my aadhar number. When I asked him how should I do it, he suggested that by sending an SMS to 121 and I need to send text "SIM 899100090002976911777U" in SMS. This could be some kind of SIM cloning or blocking techniques and might be used to get the OTP from bank or any other institution. So be careful.
