For me the domainname with dot at the end doesnt load any certificate, it simple shows the standard message "
Your connection is not secure. The owner of longb.com.br. has configured their website improperly. (...)"
And why the heck would you put a dot at the end? Or is this maybe a new...
A few links for checking DNS propagation, if you not want to wait 24-48 hours:
https://www.whatsmydns.net/
https://dnschecker.org/
https://dnspropagation.net/
Here are a few ways starting from CentOS 7 .. https://almalinux.org/elevate/
And did you try to ask in the CSF forum about the firewall problems in Centos Stream9 ? https://forum.configserver.com/
According to this site https://configserver.com/configserver-security-and-firewall/ CSF should work on CentOS v7 to v9. Maybe you want to ask there in the boards.
The site seems to have some problems, yesterday it was fine. When i call it in the browser, i also now get blank page. When i go to another site and then back in browser, then it works. In Waybackmachine its here...
https://www.web-development-blog.com/limit-the-number-of-downloads-per-client/
Beside that, only a not-so-easy way with htaccess come into my mind, setting cookie with expire(max age) in htaccess, and mod_rewrite to file or errormessage, but dont ask me how...