smtp.dominioabsoluto.com has no MX records.
Question and response
Question
dig smtp.dominioabsoluto.com. MX
Answer
The response has no answer records.
Authority
dominioabsoluto.com. 7200 SOA ns1.dominioabsoluto.com. hostmaster.ns1.dominioabsoluto.com. 1772244963 14400 3600 604800 7200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0