mail.GESEMP.CL has no CNAME records.
Question and response
Question
dig mail.GESEMP.CL. NS
Answer
The response has no answer records.
Authority
GESEMP.CL. 586 SOA bayan.ns.cloudflare.com. dns.cloudflare.com. 2395448366 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0