Apex domains cannot have CNAME records.
Question and response
Question
dig one. NS
Answer
one. 5 NS b.nic.one.
one. 5 NS x.nic.one.
one. 5 NS z.nic.one.
one. 5 NS y.nic.one.
one. 5 NS c.nic.one.
one. 5 NS a.nic.one.
Authority
The response has no authority records.
Additional
a.nic.one. 12280 A 37.209.192.9
b.nic.one. 12280 A 37.209.194.9
c.nic.one. 12280 A 37.209.196.9
x.nic.one. 12280 A 156.154.172.82
y.nic.one. 12280 A 156.154.173.82
z.nic.one. 12280 A 156.154.174.82
a.nic.one. 12280 AAAA 2001:dcd:1:0:0:0:0:9
b.nic.one. 12280 AAAA 2001:dcd:2:0:0:0:0:9
c.nic.one. 12280 AAAA 2001:dcd:3:0:0:0:0:9
x.nic.one. 12280 AAAA 2610:a1:1074:0:0:0:1:82
y.nic.one. 12280 AAAA 2610:a1:1075:0:0:0:1:82
z.nic.one. 12280 AAAA 2610:a1:1076:0:0:0:1:82
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0