To verify the number of allocated and used licenses:

  • Navigate to Setup->Build->Installed Packages

  • Verify the license status, expiration date, allowed and used licenses

If the Allowed Licenses column says Unlimited then you are either in a sandbox org, or you have a site license. 

If it shows a number, you can assign licenses to individual users by: 

  • Clicking the Manage Licenses link next to the Decisions on Demand app
  • Using the Add Users and Remove Multiple Users buttons to modify the licensed users.
    You can also click the Remove link next to individual users.