mx-relay04a.amocrm.ru has no MX records.
Question and response
Question
dig mx-relay04a.amocrm.ru. MX
Answer
The response has no answer records.
Authority
amocrm.ru. 600 SOA ns3-l2.nic.ru. dns.nic.ru. 2017055569 1440 3600 2592000 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0