sns.gtt.net has no NS records.
NS records for this zone are defined at gtt.net.
NS records for this zone are defined at gtt.net.
Question and response
Question
dig sns.gtt.net. NS
Answer
The response has no answer records.
Authority
gtt.net. 1800 SOA betty.ns.cloudflare.com. dns.cloudflare.com. 2398824520 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0