I have the following structure:

* `/projects` (archive of cpt `projects` with template `archive-projects.php`)
* `/projects/project-1` (single view of cpt with template `single-projects.php`)
* `/projects/downloads` (this is a page)

When I try to open `/projects/downloads` I get an 404 error.
Is there a way to set a page in the custom post type hierarchy?