smtp3.quick.net.au has no CNAME records.
Question and response
Question
dig smtp3.quick.net.au. NS
Answer
The response has no answer records.
Authority
quick.net.au. 876 SOA dns1.quick.net.au. domains.ddns.com.au. 2026022801 10800 900 1209600 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0