NS4.ASNIC.UK has no CNAME records.
Question and response
Question
dig NS4.ASNIC.UK. NS
Answer
The response has no answer records.
Authority
ASNIC.UK. 600 SOA ns65.domaincontrol.com. dns.jomax.net. 2025112804 28800 7200 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0