stackhero-network.com has no MX records.
Question and response
Question
dig stackhero-network.com. MX
Answer
The response has no answer records.
Authority
stackhero-network.com. 180 SOA dns-usw1za.stackhero.io. dns.stackhero-network.com. 2026045444 10800 3600 604800 180
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0