ns3.demysdns.net has no MX records.
Question and response
Question
dig ns3.demysdns.net. MX
Answer
The response has no answer records.
Authority
demysdns.net. 3600 SOA ns0.demysdns.net. dnstech.comlaude.com. 1636461879 43200 7200 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0