Apex domains cannot have CNAME records.
Question and response
Question
dig unr.hosting. NS
Answer
unr.hosting. 5 NS ns02.trs-dns.com.
unr.hosting. 5 NS ns02.trs-dns.net.
unr.hosting. 5 NS a.ns.unr.com.
unr.hosting. 5 NS b.ns.unr.com.
Authority
The response has no authority records.
Additional
ns02.trs-dns.com. 5 A 64.96.1.2
ns02.trs-dns.net. 5 A 64.96.2.2
ns02.trs-dns.com. 5 AAAA 2620:57:4001:0:0:0:0:2
ns02.trs-dns.net. 5 AAAA 2620:57:4002:0:0:0:0:2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0