ded12c.envioep.com has no MX records.
Question and response
Question
dig ded12c.envioep.com. MX
Answer
The response has no answer records.
Authority
envioep.com. 1800 SOA gemma.ns.cloudflare.com. dns.cloudflare.com. 2397112438 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0