NGINX - IPV6 - Switching default server breaks Nginx configuration

SYSTEM INFORMATION
OS type and version Rocky Linux 9.5
Usermin version 2.102
Virtualmin version 7.30.4
Theme version 21.20.7
Nginx version 1.20.1
Package updates All installed packages are up to date

My system has both ipv4 and ipv6 active. When I changed the default server of Nginx (Virtualmin > Domain > Website Options > [Default website for IP address] > Yes) then Nginx gives error and does not pass testing the new configuration file, saying there is a duplicate of default_server. I noticed that it changed the ipv4 settings but not the ipv6, both for http and ssl I had to remove the default_server to fix it.

So it is fixed but I am just reposting it as a bug.