Scheduler Licenses?

We have Zoom for Business, which includes Scheduler, and I have been working through the setup process to use Zoom Scheduler to replace another third-party scheduling service.  When attempting to add members to a Team, some members cannot be added to a team, while others can.  This warning appears on the user: "This user has an invalid license. Please assign a scheduler license to them or remove them to continue."  As far as I can tell, all users have the same licenses assigned (Zoom Workplace Business, Zoom Phone Basic).  I don't see anything that makes users different.  What am I missing?  Is there a place in Zoom to assign Scheduler licenses?