mx.transmail.com has no NS records.
NS records for this zone are defined at transmail.com.
NS records for this zone are defined at transmail.com.
Question and response
Question
dig mx.transmail.com. NS
Answer
The response has no answer records.
Authority
transmail.com. 600 SOA ns1.vtitan.com. dnsadmin.vtitan.com. 2026022203 7200 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0