Commit page asking for login

We are running a self-hosted GitLab Enterprise Edition 13.12.15-ee.

Amoungst all of our repository, this one is the only repository that keeps asking for UN/PW every time you view the specific commit page. It does this behavior in all the branches.

What I can confirm is that, the User that tries to view this page is authenticated. Tried re-login, clear-cache, the incognito-browser. Other users are also getting this behavior when viewing the commit page of the repository.

Not sure if someone else had encounter this before, but I’d like to know what could be the setting(s) that’s triggering it and how does it get disabled?