ns3.ensync.net has no MX records.
Question and response
Question
dig ns3.ensync.net. MX
Answer
The response has no answer records.
Authority
ensync.net. 86400 SOA ns1.ensync.net. dns-admin.ensync.co.za. 2022100500 7200 7200 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0