Apex domains cannot have CNAME records.
Question and response
Question
dig clear.net.nz. NS
Answer
clear.net.nz. 4 NS dns1.clear.net.nz.
clear.net.nz. 4 NS dns2.clear.net.nz.
Authority
The response has no authority records.
Additional
dns1.clear.net.nz. 4 A 203.97.33.1
dns2.clear.net.nz. 4 A 203.97.37.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0