Licence issue

I want to install the license but I am unable to do so. It is the same machine I was trying to use the license. At first Mode solution was working but not FDTD, so I deactivated the license and installed both FDTD and mode solution. When I was trying to use the “activation code” after installation I got the following error message.

Please, help me to solve the issue.


As the error indicates:
"The activation code has already been used to activate your license"

The license was not deactivated properly or was not deactivated using the method outlined on our KB:
Node license deactivation

Currently, your license is still showing as “Activated” in our servers. Most recent Activation was done on April 23, 2019. Kindly try to deactivate the license properly using the method shown from the link above.