Centerprise client not getting activated on a valid license

I have a valid license for Astera Centerprise 8 and I have been trying to activate a client on one of my colleagues’ machines but it keeps giving me the following error:


Looks like you have reached the limit of client activation on your license. You might have left one of the unattended machines activated on your license.

You can deactivate the already activated machines by logging in as an admin and following these steps:

In the top menu bar, go to Tools > Manage Client Activation > Deactivate

Once done, you should be able to activate the client on another machine.