From the PC where erwin 9.8 DM is installed, go to this directory C:\ProgramData\erwin\Data Modeler\Licensing
Delete what's inside the Licensing folder
Start erwin DM 9.8. Click the Offline activation code and send the code to erwin DM Support to generate a new activation certificate to import.
erwin support will then send you a new code which you can import into erwin and the application will start.