ip128.204.187.63.nas.net has no MX records.
Question and response
Question
dig ip128.204.187.63.nas.net. MX
Answer
The response has no answer records.
Authority
nas.net. 10800 SOA nsah.dns.nas.net. dnsadmin.nas.net. 2026021201 10800 3600 1209600 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0