What can cause a 404 error at sitename.ru/robots.txt?

Question

CMS

Hello!
I have such a problem. The site has CMS Wordpress installed. The robots.txt file is located in the root of the site, but when you click on a direct link, a 404 error is generated. The site had security plugins, there is a suspicion that somewhere there was a ban on direct access to a file or files of this type. Nothing is written in .htaccess. Please tell me what could be the reason, where to look?
.htaccess file listing
# BEGIN WordPress
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
# END WordPress

Answer 1

The reason may become clear after bringing the .htaccess code here and when the virtualserver

Answer 2

WordPress does a great job of generating a virtual "robots.txt" that can be accessed both manually via functions.php and via plugins. Most often, access to it is blocked by SEO plugins and pages with a similar name (for example, www.site_name.com/robots).