The 'Host' field contained in Http header is invalid [closed]

I tried to configure a DDNS with DynDNS.it on my router "Sercomm VD625 (AGCOMBO)" and with every browser I use I always get the same error "The 'Host' field contained in Http header is invalid" ; I have installed and configured "Apache, PHP, and MySQL" on FreeBSD 13 following this tutorial :

https://linuxhint.com/install-apache-php-mysql-on-freebsd/

to be sure that the problem wasn't caused by DDNS,I tried to write on the browser my public IP,but I've got the same error. The odd thing is that I'm forced to specify the HTTPS protocol on the address bar. If I don't use it,it adds it. Otherwise the connection is refused.

The domain is linked to the public IP correctly and the error happens when I use the domain name and / or the public IP. The DDNS is well configured,because inside the proper router section I can read "updated successfully".

When I open the website "http://192.168.1.6/" on my browser, (it's the IP number assigned to FreeBSD), I see the message "It works" ,but when I open the web "ziomario.ns0.it" I see the error "The 'Host' field contained in Http header is invalid" so I think that this error is not caused by some wrong setting correlated with the installation of "Apache, PHP, and MySQL" but maybe it is caused by some different web component that I don't know. Can someone give me some suggestion about what could be wrong ? thanks.