Yes, you will have to download the app & register for UPI sharing your details again.
Related Question
What is Freecharge UPI?
What is a UPI ID?
Does the UPI ID necessarily have to end with @freecharge?
What if someone has already created a UPI ID using my name?
What can be a UPI ID?
How will I know whether the unique ID (UPI ID) provided by the receiver is corre...
Who can use UPI on Freecharge?
What can you do using Freecharge UPI?
Is UPI available on Freecharge app on iOS, Windows and Blackberry smartphones?
Are there any charges to use UPI on Freecharge?
If I delete or uninstall Freecharge app from my mobile phone by mistake, will I have to register again?
Yes, you will have to download the app & register for UPI sharing your details again.