You can manage what devices are using active seats of ProPresenter from the Renewed Vision Account Manager. You will need to be logged into accounts.renewedvision.com and then click on the seat count from the Account Manager Dashboard. 

From the License Management page, you will click the three dots next to the machine you which to manage and then choose "Deactivate" to make the seat inactive on that machine or "Sign Out" if you want to completely sign out of ProPresenter on that machine. 

Once you complete either action, the machine you made the change on will be either set to "Inactive" or signed out entirely and you will need to change it back to "Active" or sign back in from that machine in order to reverse this action.