ns2.mldnet.com has no MX records.
Question and response
Question
dig ns2.mldnet.com. MX
Answer
The response has no answer records.
Authority
mldnet.com. 54000 SOA ns.mldnet.com. postmaster.mldnet.com. 2023081218 28800 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0