mail.calacoop.com.ar has no CNAME records.
Question and response
Question
dig mail.calacoop.com.ar. NS
Answer
The response has no answer records.
Authority
calacoop.com.ar. 3600 SOA calacoop.com.ar. info.calacoop.com.ar. 2024051602 3600 900 86400 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0