New install of Octopus Server, web portal has no options

I’m new to OD and have just installed the server product onto a clean Windows server. I’ve sorted out the bindings and now I can get to the web portal from any client PC. I log in using active directory.

But I have no menu options, just an empty dashboard.

How do I set up users and permissions etc? The documentation seems to assume that when I log in I will have full admin rights.