Key Users can overview the User Roles available on their site, and see the breakdown between Free User Roles & Key User Roles (Paid Licenses). This can be found via Settings > User Management.
The page will also show how many Key User licenses (Paid Licenses) are left to be assigned to users as needed, according to the contract. Key users will be able to allocate Key User licenses to contacts as long as there are spare licenses to be used (done via going into the relevant Contact and picking the relevant User Role).
If there are no spare Key User licenses left, please submit a request to add new licenses to your subscription via the relevant form on our HQ site.