There are two types of activations, depending on what you bought:
Classic or Subscription
Classic deactivations need to be done on the machine itself, not by deinstalling the software but by removing a license in the help menu or welcome screen.
Subscription activations can be cleared in a browser, y going into the AMP (myaccount.trimble.com) and choosing ‘My Products’ > View Included Apps > manage devices
What do you have?