Satellite 6 unused subscription is not available for attach

Issue

• Satellite shows N number of subscription used, however when we are checking the consumption, it shows (N-1) host associated.

For example, Customer has 90 of following subscription :

Red Hat Enterprise Linux for Virtual Datacenters with Smart Management, Premium

When we check the Associations -> Hosts - it shows 89 Hosts instead of 90.

• Satellite does not show the unused subscription as available for attach.