smtp.sbarailapp.com has no NS records.
NS records for this zone are defined at sbarailapp.com.
NS records for this zone are defined at sbarailapp.com.
Question and response
Question
dig smtp.sbarailapp.com. NS
Answer
The response has no answer records.
Authority
sbarailapp.com. 1800 SOA danica.ns.cloudflare.com. dns.cloudflare.com. 2395030056 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0