'api_admin' is not a registered namespace error when trying to gain api access

I am attempting to write a plugin for edx that adds more api access. However, when I attempt to work with tutor locally I get this error which stops me form enabling api access.

In the logs I get:
‘api_admin’ is not a registered namespace

When I attempt to visit

I have attempted this with the latest version of tutor and the latest v15 release.