You can assign your license to your machine by simply signing into the Maxon App and choosing the license you'd like to use to activate/assign to it.
Please ensure you have the latest version of Maxon App from the link below;
Then go to the 3 dots by the product you own, and click "Assign"
If your license is already being used by another machine, you can release it from the other machine;
How do I release a license manually?