I don't use software licenses, but my understanding is that you have to send it back to the pool from the machine it is currently on.
If you can't access this machine then I believe you can contact your Graphisoft support people and they can return the license to to the pool.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11