Why is the displayed content different on IPV6 and IPV4?

I am having problems viewing the website page as per my IPV6/IPV4 connection.

When I connect via IPV4 the site is displayed correctly.





When I connect via IPV6 the page shown is CWP standard.





Why does it happen?
Is it a problem with my computer?
This also happens with some other domains.

thanks!

Open the config files (Nginx, Apache) of the problematic website and make sure the virtual host is configured to accept connections over IPv6.

Most likely there is IPv4 address only. That is why you get the default CWP page when try to access the site over IPv6.

Look here:
https://www.mysterydata.com/enable-ipv6-cwp-centos-webpanel/
this guide will help you to understand if the problematic website has the correct webserver config files.