Hello,
this happens when the computer is built upon a pervious image or after an upgrade which changes the system ID (hardware replacement, upgrade from Windows 8 to 8.1, etc.).
The solution to this is here: https://www.steinberg.net/en/support/knowledgebase_new/show_details/kb_show/program-installation-does-not-create-a-soft-elicenser/
The article is about the Soft-eLicenser not created on a system, but forcing the system to create a new Soft-eLicenser works in these cases as well. If the Soft-eLicenser contains licenses, those will need to be reactivated after running the helper tool, as this will erase the Soft-eLicenser as well as the licenses contained.
Regards,