Apex domains cannot have CNAME records.
Question and response
Question
dig idcn.no. NS
Answer
idcn.no. 5 NS ns2.iplace.se.
idcn.no. 5 NS ns1.iplace.se.
idcn.no. 5 NS ns1.idcn.no.
idcn.no. 5 NS ns3.iplace.se.
Authority
The response has no authority records.
Additional
ns1.idcn.no. 5 A 85.19.135.208
ns1.iplace.se. 1 A 84.19.146.195
ns2.iplace.se. 1 A 193.44.15.8
ns3.iplace.se. 1 A 88.131.112.129
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0