Apex domains cannot have CNAME records.
Question and response
Question
dig sonic.net. NS
Answer
sonic.net. 5 NS b.auth-ns.sonic.net.
sonic.net. 5 NS c.auth-ns.sonic.net.
sonic.net. 5 NS d.auth-ns.sonic.net.
sonic.net. 5 NS a.auth-ns.sonic.net.
Authority
The response has no authority records.
Additional
a.auth-ns.sonic.net. 5 A 157.131.0.39
b.auth-ns.sonic.net. 5 A 75.101.68.144
c.auth-ns.sonic.net. 5 A 139.178.66.139
d.auth-ns.sonic.net. 5 A 145.40.74.236
a.auth-ns.sonic.net. 5 AAAA 2001:5a8:601:2:0:0:0:39
b.auth-ns.sonic.net. 5 AAAA 2607:43c1:1:3:0:0:0:144
c.auth-ns.sonic.net. 5 AAAA 2604:1380:45d1:ae01:0:0:0:3
d.auth-ns.sonic.net. 5 AAAA 2604:1380:4631:7e01:0:0:0:3
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0