Floating License is a preferred type of license when computer is connected to the internet.
It has multiple advandages like ability to be used on multiple computers and easier license transfers that do not invole sending an email with license-transfer request.
Here is how Floating License works:
After a floating licens eis activated on a computer it pings the license server every 10 minutes* to renew the seat.
If in the meantime the seat was requested by another computer, the seat renewal will fail and you will get an error message saying that "The seat is busy".
This usually only happens when you try use HSMAdvisor on more than one computer.
In such case consider upgrading to a 2 seat license.
You can also change how often HSMAdisor pings the server by going to Settings and choosing a different "Floating License Parking Period"
As courtesy i will reset parked seats for users who need urgent license renewals on other computers (ie: accidental choosing of longer than needed License Parking Period, or other things like changing of eployer, computer upgrades etc.)