Dial 199 or 1299 from your Jio SIM and check the IVR details
Use the MyJio app and view your number on the home screen
Send an SMS or make a call from your Jio SIM to another phone and check the caller ID
Check the SIM card pack or welcome letter if available
Call Jio customer care and ask for your number after verification
Dial *1# from your Jio number if the USSD code works on your device
Check your phone settings under SIM or About Phone if the number is saved there