Apex domains cannot have CNAME records.
Question and response
Question
dig monikerdns.net. NS
Answer
monikerdns.net. 5 NS ns1.monikerdns.net.
monikerdns.net. 5 NS ns3.monikerdns.net.
monikerdns.net. 5 NS ns2.monikerdns.net.
monikerdns.net. 5 NS ns4.monikerdns.net.
Authority
The response has no authority records.
Additional
ns1.monikerdns.net. 5 A 193.227.117.25
ns2.monikerdns.net. 5 A 194.50.187.25
ns3.monikerdns.net. 5 A 194.0.182.25
ns4.monikerdns.net. 5 A 194.0.182.25
ns1.monikerdns.net. 5 AAAA 2a04:2b00:14cc:0:0:0:0:25
ns2.monikerdns.net. 5 AAAA 2a04:2b00:14dd:0:0:0:0:25
ns3.monikerdns.net. 5 AAAA 2a04:2b00:14ee:0:0:0:0:25
ns4.monikerdns.net. 5 AAAA 2a04:2b00:14ee:0:0:0:0:25
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0