Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-22.net. NS
Answer
awsdns-22.net. 5 NS g-ns-1366.awsdns-22.net.
awsdns-22.net. 5 NS g-ns-1942.awsdns-22.net.
awsdns-22.net. 5 NS g-ns-471.awsdns-22.net.
awsdns-22.net. 5 NS g-ns-792.awsdns-22.net.
Authority
The response has no authority records.
Additional
g-ns-471.awsdns-22.net. 5 A 205.251.193.215
g-ns-792.awsdns-22.net. 5 A 205.251.195.24
g-ns-1366.awsdns-22.net. 5 A 205.251.197.86
g-ns-1942.awsdns-22.net. 5 A 205.251.199.150
g-ns-471.awsdns-22.net. 5 AAAA 2600:9000:5301:d700:0:0:0:1
g-ns-792.awsdns-22.net. 5 AAAA 2600:9000:5303:1800:0:0:0:1
g-ns-1366.awsdns-22.net. 5 AAAA 2600:9000:5305:5600:0:0:0:1
g-ns-1942.awsdns-22.net. 5 AAAA 2600:9000:5307:9600:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0