Apex domains cannot have CNAME records.
Question and response
Question
dig securepay.com.au. NS
Answer
securepay.com.au. 5 NS ns-860.awsdns-43.net.
securepay.com.au. 5 NS ns-98.awsdns-12.com.
securepay.com.au. 5 NS ns-1931.awsdns-49.co.uk.
securepay.com.au. 5 NS ns-1050.awsdns-03.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0