Can't point InfinityFree DNS

Hi and welcome to the forum! Seems like you’re trying to change the nameservers on an .it domain, which won’t work out for the registry’s side because of this error:

though has a bug where it’ll always be stuck on the “Nameserver changing” phase as the registry refused the nameserver changing because there are no DNS records for the nameservers, and we only set the records after the domain has been added to an account. In short: for now you can’t host your .it domain, until in the future there will be an A record verification to add a domain.