Paid for pro but only have one license

Hello, 

My organisation has the Pro version of Zoom. The website says that this allows us to have up to nine licenses. However, we only have one user, and when I try to add another user, it says there are no more licenses available and that I need to buy more. Then when I clicked on "purchase more licenses" it took me to a page to upgrade my account. I don't understand why I need to upgrade my account, if 9 licenses are included in pro. 

Can anyone help?

Many thanks