Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-47.com. NS
Answer
awsdns-47.com. 5 NS g-ns-1199.awsdns-47.com.
awsdns-47.com. 5 NS g-ns-48.awsdns-47.com.
awsdns-47.com. 5 NS g-ns-623.awsdns-47.com.
awsdns-47.com. 5 NS g-ns-1775.awsdns-47.com.
Authority
The response has no authority records.
Additional
g-ns-48.awsdns-47.com. 5 A 205.251.192.48
g-ns-623.awsdns-47.com. 5 A 205.251.194.111
g-ns-1199.awsdns-47.com. 5 A 205.251.196.175
g-ns-1775.awsdns-47.com. 5 A 205.251.198.239
g-ns-48.awsdns-47.com. 5 AAAA 2600:9000:5300:3000:0:0:0:1
g-ns-623.awsdns-47.com. 5 AAAA 2600:9000:5302:6f00:0:0:0:1
g-ns-1199.awsdns-47.com. 5 AAAA 2600:9000:5304:af00:0:0:0:1
g-ns-1775.awsdns-47.com. 5 AAAA 2600:9000:5306:ef00:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0