certtest.is.cc has no NS records.
NS records for this zone are defined at is.cc.
NS records for this zone are defined at is.cc.
Question and response
Question
dig certtest.is.cc. NS
Answer
The response has no answer records.
Authority
is.cc. 1800 SOA josh.ns.cloudflare.com. dns.cloudflare.com. 2397166473 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0