Apex domains cannot have CNAME records.
Question and response
Question
dig nethome.no. NS
Answer
nethome.no. 5 NS ns4.itsjefen.no.
nethome.no. 5 NS ns3.itsjefen.no.
nethome.no. 5 NS ns5.itsjefen.no.
Authority
The response has no authority records.
Additional
ns3.itsjefen.no. 5 A 92.62.33.9
ns4.itsjefen.no. 5 A 92.62.33.112
ns5.itsjefen.no. 5 A 93.89.112.213
ns3.itsjefen.no. 5 AAAA 2a02:2c8:1:400:0:0:0:3309
ns4.itsjefen.no. 5 AAAA 2a02:2c8:1:400:0:0:0:112
ns5.itsjefen.no. 5 AAAA 2a02:25e8:1:12:0:0:0:113
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0