Staff Accepted Invite but Still Not Bookable

Our organization is having issues with assigning team members that do not have an associated Bookings license as Team Member staff on a service of a Bookings page owned by a licensed team member.  It appears there are a couple other threads in this community that are having the same issue but no resolution or root cause is mentioned. 

The use case is that we assign a Bookings license to a team member.  When the licensed team member creates a staff record (from an active team member inside our organization) as a Team Member, the invited staff accept the invitation email and are directed to a generic page (screen shot directly below).

Although the staff member has accepted, their staff record in Bookings administration cannot be booked.  Their staff record status is 'Not Bookable'.  This will prevent our organization from adopting MS Bookings. 

Please advise!

Ben Lewis