ns1.isota.io has no MX records.
Question and response
Question
dig ns1.isota.io. MX
Answer
The response has no answer records.
Authority
isota.io. 3600 SOA isota.io. root.isota.io.isota.io. 2026030307 604800 86400 2419200 604800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0