correo.ipnext.com.ar has no CNAME records.
Question and response
Question
dig correo.ipnext.com.ar. NS
Answer
The response has no answer records.
Authority
ipnext.com.ar. 3600 SOA dns1.ipnext.com.ar. webmaster.ipnext.com.ar. 2025082201 7200 540 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0