mx.myusajobs.com has no NS records.
NS records for this zone are defined at myusajobs.com.
NS records for this zone are defined at myusajobs.com.
Question and response
Question
dig mx.myusajobs.com. NS
Answer
The response has no answer records.
Authority
myusajobs.com. 3600 SOA dns.myusajobs.com. hostmaster.myusajobs.com. 1615204581 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0