Call Airtel customer care from another phone and request SIM blocking
Dial the Airtel helpline number for your country and follow the IVR to report a lost or stolen SIM
Visit the nearest Airtel store or service center with valid ID proof and request SIM deactivation
Use the Airtel Thanks app or Airtel website if your country supports SIM block requests online
Provide your mobile number, registered name, and identity verification details
Ask customer care to block the SIM immediately if it is lost, stolen, or compromised
Request a duplicate SIM after the old SIM is blocked if you want to keep the same number
Keep the SIM block request reference number for follow-up
If your phone was stolen, also block the IMEI through your device manufacturer or police report process if applicable