_dc-mx.d1e52dfc73c6.izonesoftware.com has no CNAME records.
Question and response
Question
dig _dc-mx.d1e52dfc73c6.izonesoftware.com. NS
Answer
The response has no answer records.
Authority
izonesoftware.com. 1605 SOA igor.ns.cloudflare.com. dns.cloudflare.com. 2398280479 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0