You need to download and register for UPI on Freecharge on the new device.
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?
What if I change my mobile handset and want to use Freecharge UPI on the new device with the same number?
You need to download and register for UPI on Freecharge on the new device.