Firstly check that you have the right permissions/roles to perform this task. If not speak to your Main Administrator at the school.
Go to Students.
Select the student you want to add the new UPN to, make sure the student is highlighted and press View.
Once in View go to Enrolment.
At the right hand side, there should be 'Key Data', press the little pencil icon.
Go to UPN and press the magnifier glass icon, when you hover over it, it will ask to create a new UPN.
Go through the steps to creating a new UPN and then select Save.
Any issues let us know by emailing email@example.com or calling us on 01527 359 999.