ns3.ni has no MX records.
Question and response
Question
dig ns3.ni. MX
Answer
The response has no answer records.
Authority
ni. 3600 SOA ns.ni. root.ns.ni. 2021131277 600 900 604801 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0