securemail.seppmail365.com has no CNAME records.
Question and response
Question
dig securemail.seppmail365.com. NS
Answer
The response has no answer records.
Authority
seppmail365.com. 18 SOA ns1.nodesecure.com. do-not-reply.seppmail365.com. 2025025031 43200 7200 1209600 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0