alyssa51.bitcommand.com has no MX records.
Question and response
Question
dig alyssa51.bitcommand.com. MX
Answer
The response has no answer records.
Authority
bitcommand.com. 1800 SOA eva.ns.cloudflare.com. dns.cloudflare.com. 2397740221 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0