admin.lianamailer.com has no MX records.
Question and response
Question
dig admin.lianamailer.com. MX
Answer
The response has no answer records.
Authority
lianamailer.com. 1800 SOA ian.ns.cloudflare.com. dns.cloudflare.com. 2395938953 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0