it doesn't block any content

I believe there is an issue associated with the settings of the plugin.

I’ve found that i do not have issues if i leave the following to their default values:
1. login page
2. register page
3. user profile page.

I start running into the same problem whenever I select a page for each of these categories.

Let me know if you have a similar issue.

Since I don’t really know what you are doing nor what your expectation is, I would suggest starting with the Quick Start Guide:
https://rocketgeek.com/plugins/wp-members/quick-start-guide/

Here are some additional links with info on this topic:
https://rocketgeek.com/plugins/wp-members/docs/managing-content/
https://rocketgeek.com/plugins/wp-members/docs/faqs/
https://rocketgeek.com/blog/how-the-plugin-handles-blocking-content/

Wow, dear moderninfluence, yes, I had the similar problem. I left the dafault settings at login page – and abracadabra – it blocks everything, I wanted. Blog posts, pages.
It works!
Moderninfuluence, Chad – thank you for your quick help!