o2000.prima.com.ar has no CNAME records.
Question and response
Question
dig o2000.prima.com.ar. NS
Answer
The response has no answer records.
Authority
prima.com.ar. 3329 SOA o200.prima.com.ar. dnsmaster.prima.com.ar. 2017011706 3600 900 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0