License Manager is not functioning

[COMPASS_DEUEL]

I have C3D on my home PC and have been working from home all week. When I log into my office PC and open C3D (I have already closed C3D on my home PC) I get the error message "The license manager is not functioning or is improperly installed. AutoCAD will shut down now." How can I fix this?

On the work PC I have already gone into Services: Flex net license....   It is already enabled.  

I am running C3D 2019, windows 10, 64 bit.

Your help would be appreciated, thanks

[DarrenP]

for 2017 to 2019 try this: https://knowledge.autodesk.com/support/autocad/troubleshooting/caas/sfdcarticles/sfdcarticles/AutoCA...