How Apex Planner license works
Each license is bound to a single organization: it can be used only for the CRM organization on which it was activated. The license key limits the number of users and the time interval. You can see the maximum number of users allowed and the expiration date on the Global Configuration.
Suppose that you have a license for 50 users that expires on January 1. If your organization has more than 50 active users or if the current date is over January 1, the Planner reports an error. You will see in the next paragraphs how to limit the number of users that you need to license.