Field value is not displayed while data is present in db

I am having a weird issue I cannot understand.

My database:
Newsletter has one Author
Author has 0 or many Newsletters
An Author has a username.

When displaying the newsletter, I want to display the Author’s username. All authors have a username in database.
However the value is not displayed.

Have you ever faced a similar issue?

Hi there,… the issue could be related to privacy rules. Do you have any rules in place on the Author data type that would prohibit authors from seeing other authors’ usernames?