I have tried creating another registration page with the shortcode.
Same result for me.
This is the second time that I get this problem.
The previous time was on another site. I had to scrap everything and start over.
This time I’m going to use a different plugin for membership.
Same problem here.
Have uninstalled UM several times and always the same result.
The registration page redirects to the login page.
Except when I’m logged in.
It worked for a few people Friday morning then halfway through the day on Friday it stopped working.
Nothing was changed on the site when it stopped working.