To deactivate a licence on another machine, you can get access to the Licence Manager through the Software Alliance website: https://www.softwarealliance.net/.
To do this, do the following:
1. Navigate to https://www.softwarealliance.net/ and click Sign In.
2. Enter your email address and password and click sign in.
3. Once you have logged in, click on the Support drop-down list and click Licence Manager.
4. Select the View Activations button on the required licence to view the activated machines.
5. To deactivate an activated instance, click the Deactivate button.
Once deactivated, you can then activate the licence on another machine or another user as required.