mailsec.telemaxx.net has no CNAME records.
Question and response
Question
dig mailsec.telemaxx.net. NS
Answer
The response has no answer records.
Authority
telemaxx.net. 10504 SOA ns01.telemaxx.net. do-not-reply.telemaxx.net. 2025120507 43200 7200 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0