Apex domains cannot have CNAME records.
Question and response
Question
dig dns.Id. NS
Answer
dns.Id. 5 NS b.dns.Id.
dns.Id. 5 NS d.dns.Id.
dns.Id. 5 NS c.dns.Id.
dns.Id. 5 NS e.dns.Id.
Authority
The response has no authority records.
Additional
b.dns.id. 89265 A 103.19.179.179
c.dns.id. 106866 A 103.19.178.178
d.dns.id. 94964 A 45.126.57.57
e.dns.id. 106866 A 103.19.177.177
b.dns.id. 89265 AAAA 2402:ee80:b:0:0:0:0:b
c.dns.id. 106866 AAAA 2402:ee80:c:0:0:0:0:c
d.dns.id. 94964 AAAA 2402:ee80:d:0:0:0:0:d
e.dns.id. 106866 AAAA 2001:df5:4000:4:0:0:0:4
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0