mail19.thaibombmail.com has no NS records.
NS records for this zone are defined at thaibombmail.com.
NS records for this zone are defined at thaibombmail.com.
Question and response
Question
dig mail19.thaibombmail.com. NS
Answer
The response has no answer records.
Authority
thaibombmail.com. 1800 SOA beth.ns.cloudflare.com. dns.cloudflare.com. 2398417413 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0