mail.unifiedlayer.com has no MX records.
Question and response
Question
dig mail.unifiedlayer.com. MX
Answer
The response has no answer records.
Authority
mail.unifiedlayer.com. 300 SOA ns1.unifiedlayer.com. root.unifiedlayer.com. 2021072800 28800 14400 3600000 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0