mail.netsons.com has no NS records.
NS records for this zone are defined at netsons.com.
NS records for this zone are defined at netsons.com.
Question and response
Question
dig mail.netsons.com. NS
Answer
The response has no answer records.
Authority
netsons.com. 1800 SOA jim.ns.cloudflare.com. dns.cloudflare.com. 2398838278 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0