Login screen is not really a login screen

Hello,

I have transferred my site from WP to Grav and am struggling with one thing (everything else I’ve found answers for in the forum). I’m using Grav 1.57 and the Antimatter theme. I have a public page 01.home/ and a private, password protected blog, 02.blog/. Login plugin is installed and 02.blog/blog.md has

access:
  site.login: true

If I set the webroot to /blog and click on the link then I get what I expect to see, a screen titled User Login and two fields for username and password (cannot post image, I’m limited to one only as a new user) but if I set the webroot to /home and click on the link for blog I see the screen below

which, despite the title, does not allow a user to login, why am I seeing this second page and/or how do I force the first page to be shown instead?