Thanks for being a longtime FloorPlan customer.
I'd love to assist, unfortunately, the version of FloorPlan you're using is no longer supported. The license server used for the unsupported versions is obsolete and may not be reactivated. I recommend upgrading the program to the current version for operating system support, numerous features and improvements over the years.
You can see upgrade options here -
Windows: https://www.turbocad.com/content/floorplan-upgarde-center
Mac: https://www.turbocad.com/content/floorplan-upgrade-center-mac