Doc Maker greyed out of "Add Page" if I lock a page in the Doc

Hi everyone, the title says it all already. I have a doc in a shared folder with 30ish pages+subpages. 1 page and 1 subpage I have locked to “Interact only”, with only “Comment” and “Use buttons, controls, and forms” enabled.

I am the doc maker and admin and have no issues with adding new pages. But my other test doc maker (non-admin) account cannot add new pages, as the option is just greyed out. Other non-admin doc makers also face the same issue on my team.

Has anyone experienced anything similar? Thanks a bunch!

Are they editors or doc makers?

And are they trying to add subpages to the locked page? Or just new pages altogether?

They are doc makers, adding pages or subpages anywhere is greyed out, not just the locked pages.