Question : DNS Server Update

I'm trying to update the nameservers on a domain that is an argentina extension..www.site.com.ar. However, when I try to save the nameservers, I get the following error..

Your new DNS server information was NOT saved.

Domain Authority for this domain requires that your DNS servers respond in an authoritative way to your Domain. The servers that you entered are not responding this way; please contact your host provider so they fix this, then try the update again.

Query refused

Server Error:
Query refused

Any idea why that would happen?  Could it be that the host I'm pointing to is blocked it because it's an argentina TLD?

Answer : DNS Server Update

Whichever name servers you're putting in are refusing to answer the query for "www.site.com.ar".

Presumably that exists as a Forward Lookup Zone on those servers?

Chris