mx.hfhofdelta.com has no NS records.
NS records for this zone are defined at hfhofdelta.com.
NS records for this zone are defined at hfhofdelta.com.
Question and response
Question
dig mx.hfhofdelta.com. NS
Answer
The response has no answer records.
Authority
hfhofdelta.com. 3600 SOA dns.hfhofdelta.com. hostmaster.hfhofdelta.com. 1960168963 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0