smtp.misterfly.com has no NS records.
NS records for this zone are defined at misterfly.com.
NS records for this zone are defined at misterfly.com.
Question and response
Question
dig smtp.misterfly.com. NS
Answer
The response has no answer records.
Authority
misterfly.com. 1800 SOA aron.ns.cloudflare.com. dns.cloudflare.com. 2398741967 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0