UNASSIGNED.core.vf.net.nz has no CNAME records.
Question and response
Question
dig UNASSIGNED.core.vf.net.nz. NS
Answer
The response has no answer records.
Authority
vf.net.nz. 300 SOA ns1.one.nz. dg-nz-ipnetworknz.one.nz. 2026022401 3600 900 3600000 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0