gbdc61.nubenet.com.ar has no MX records.
Question and response
Question
dig gbdc61.nubenet.com.ar. MX
Answer
The response has no answer records.
Authority
nubenet.com.ar. 86400 SOA ns1.nubehost.com.ar. admin.nubenet.com.ar. 2026012102 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0