Require login for specific media object (PDF)

I am trying to require a subscriber login to access a specific PDF in my site’s media library. If I click on the media content (a PDF) > click ‘Edit more details’ > change ‘Require login to view this content?’ to ‘Yes’ > change ‘Login type’ to ‘subscriber’ > click ‘Update’, I get a message stating ‘Media file updated’ at the top of the screen. However, the ‘Require login to view this content?’ resets to the default ‘No’ and a login is not enforced in order to access the document.

I really enjoy this plugin and I’m hoping there is a way to fix the functionality when trying to apply it to an individual media item so that I don’t have to content block an entire page. 🙂

Thank you!