Apex domains cannot have CNAME records.
Question and response
Question
dig no. NS
Answer
no. 5 NS y.nic.no.
no. 5 NS i.nic.no.
no. 5 NS not.norid.no.
no. 5 NS njet.norid.no.
no. 5 NS x.nic.no.
no. 5 NS z.nic.no.
Authority
The response has no authority records.
Additional
i.nic.no. 160469 A 194.146.106.6
x.nic.no. 82395 A 128.39.8.40
y.nic.no. 160381 A 193.75.4.22
z.nic.no. 154998 A 158.38.8.133
not.norid.no. 107788 A 156.154.100.12
njet.norid.no. 135772 A 156.154.101.12
i.nic.no. 160469 AAAA 2001:67c:1010:1:0:0:0:53
x.nic.no. 82395 AAAA 2001:700:0:412f:0:0:0:40
y.nic.no. 160381 AAAA 2001:8c0:8200:1:0:0:0:2
z.nic.no. 154998 AAAA 2001:700:0:52d:158:38:8:133
not.norid.no. 107788 AAAA 2001:502:ad09:0:0:0:0:12
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0