gulp.arnet.com.ar has no NS records.
NS records for this zone are defined at arnet.com.ar.
NS records for this zone are defined at arnet.com.ar.
Question and response
Question
dig gulp.arnet.com.ar. NS
Answer
The response has no answer records.
Authority
arnet.com.ar. 300 SOA jazzy.arnet.com.ar. dnsmaster.arnet.net.ar. 3008091073 86400 7200 3600000 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0