mail.retrocogni.com has no MX records.
Question and response
Question
dig mail.retrocogni.com. MX
Answer
The response has no answer records.
Authority
retrocogni.com. 3600 SOA ns1.retrocogni.com. ns2.retrocogni.com. 1744779850 7200 3600 1209600 3600
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0