Dial *121# from your Airtel SIM and check the menu for your number
Dial *282# to display your Airtel mobile number
Call or message another phone and check the caller ID or received SMS
Check the SIM card pack or documents if you still have them
Open the Airtel Thanks app if your number is already linked
Check your phone settings under SIM or About Phone
Contact Airtel customer care from your Airtel number or another phone
Visit an Airtel store with valid ID for assistance