ns3.sdns.network has no MX records.
Question and response
Question
dig ns3.sdns.network. MX
Answer
The response has no answer records.
Authority
sdns.network. 120 SOA ns1.sdns.network. hostmaster.sdns.network. 2023101404 21600 3600 604800 120
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0