Apex domains cannot have CNAME records.
Question and response
Question
dig naamserver.net. NS
Answer
naamserver.net. 5 NS ns2.naamserver.net.
naamserver.net. 5 NS ns.naamserver.net.
naamserver.net. 5 NS ns1.naamserver.net.
Authority
The response has no authority records.
Additional
ns.naamserver.net. 5 A 185.103.159.158
ns1.naamserver.net. 5 A 185.94.228.152
ns2.naamserver.net. 5 A 92.63.173.169
ns.naamserver.net. 5 AAAA 2a00:f10:400:4:1c00:aff:fe00:169c
ns1.naamserver.net. 5 AAAA 2a05:1500:501:1:1c00:67ff:fe00:108
ns2.naamserver.net. 5 AAAA 2a05:1500:702:3:1c00:d2ff:fe00:14b2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0