v2-a20.hrdns.info has no MX records.
Question and response
Question
dig v2-a20.hrdns.info. MX
Answer
The response has no answer records.
Authority
hrdns.info. 300 SOA ns1.name.com. hostmaster.nsone.net. 1652913370 7200 3600 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0