Get the old apk of MyJio app from below link
Install MyJio and then all 11 applications from app store do not open any application
Turn off your data/wifi
Open MyJio app, then click on MyJio again.
You will see 3 options Get Jio SIM, Sign In and Sign Up.
Select Sign in
Enter you Jio ID and Password. You can generate your Jio ID by linking your Jio number with email ID on Jio.com.
Do not click on Sign In. Just enter the ID and Password.
Trun on the data/wifi
Click on Sign In.
You have to try couple of times to get to the next screen where it will ask you for submit.
Once you get the submit button click that and that's all. Your unlimited offer is credited.
Enjoy unlimited Digital life for 3 months. Please your story on the comments below.