Apex domains cannot have CNAME records.
Question and response
Question
dig Id. NS
Answer
id. 1 NS e.dns.Id.
id. 1 NS b.dns.Id.
id. 1 NS d.dns.Id.
id. 1 NS c.dns.Id.
id. 1 NS ns4.apnic.net.
Authority
The response has no authority records.
Additional
b.dns.id. 44532 A 103.19.179.179
c.dns.id. 62133 A 103.19.178.178
d.dns.id. 50231 A 45.126.57.57
e.dns.id. 62133 A 103.19.177.177
ns4.apnic.net. 1 A 202.12.31.53
b.dns.id. 44532 AAAA 2402:ee80:b:0:0:0:0:b
c.dns.id. 62133 AAAA 2402:ee80:c:0:0:0:0:c
d.dns.id. 50231 AAAA 2402:ee80:d:0:0:0:0:d
e.dns.id. 62133 AAAA 2001:df5:4000:4:0:0:0:4
ns4.apnic.net. 1 AAAA 2001:dd8:12:0:0:0:0:53
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0