mx.shopatcarbon.com has no NS records.
NS records for this zone are defined at shopatcarbon.com.
NS records for this zone are defined at shopatcarbon.com.
Question and response
Question
dig mx.shopatcarbon.com. NS
Answer
The response has no answer records.
Authority
shopatcarbon.com. 3600 SOA dns.shopatcarbon.com. hostmaster.shopatcarbon.com. 1549097078 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0