Dial `*222#` from your BSNL SIM
Dial `*888#` from your BSNL SIM
Call `1503` or `1800-180-1503` and ask customer care
Check the SIM card pack or welcome letter
Open the BSNL mobile app or account details if already registered
Call another phone from your BSNL number and check the caller ID
Send an SMS or missed call from your BSNL number to another phone and note the displayed number
Check your phone settings under SIM details or About phone if the number is saved there