helium.melitacable.com has no MX records.
Question and response
Question
dig helium.melitacable.com. MX
Answer
The response has no answer records.
Authority
melitacable.com. 86400 SOA helium.melitacable.com. domains.melitacable.com. 2025123001 28800 7200 2419200 86400
Additional
. 0 OPT [{Extended_DNS_Error: PROHIBITED}] ; payload 1232, xrcode 0, version 0, flags 0