Unable to See All Users

I am an Admin and I'm attempting to remove 1 user and add another user. When I navigate to Users> User Permissions, the only user I see is my name, even though I know we have another user. Additionally, when I try to add a user, I am told I do not have a sufficient number of licenses despite having 5 licenses. I have navigated through all of our roles and I still only see my name as a user.