Apex domains cannot have CNAME records.
Question and response
Question
dig ipng.net.au. NS
Answer
ipng.net.au. 5 NS ns3.nameserver.net.au.
ipng.net.au. 5 NS ns2.nameserver.net.au.
ipng.net.au. 5 NS ns1.nameserver.net.au.
Authority
The response has no authority records.
Additional
ns1.nameserver.net.au. 5 A 112.140.176.177
ns2.nameserver.net.au. 5 A 103.252.154.10
ns3.nameserver.net.au. 5 A 45.79.92.84
ns1.nameserver.net.au. 5 AAAA 2400:b800:0:1:0:0:0:11
ns2.nameserver.net.au. 5 AAAA 2400:8f80:0:11:0:0:0:107
ns3.nameserver.net.au. 5 AAAA 2600:3c01:0:0:f03c:93ff:fed1:8135
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0