Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-37.org. NS
Answer
awsdns-37.org. 5 NS g-ns-743.awsdns-37.org.
awsdns-37.org. 5 NS g-ns-1637.awsdns-37.org.
awsdns-37.org. 5 NS g-ns-165.awsdns-37.org.
awsdns-37.org. 5 NS g-ns-1064.awsdns-37.org.
Authority
The response has no authority records.
Additional
g-ns-165.awsdns-37.org. 5 A 205.251.192.165
g-ns-743.awsdns-37.org. 5 A 205.251.194.231
g-ns-1064.awsdns-37.org. 5 A 205.251.196.40
g-ns-1637.awsdns-37.org. 5 A 205.251.198.101
g-ns-165.awsdns-37.org. 5 AAAA 2600:9000:5300:a500:0:0:0:1
g-ns-743.awsdns-37.org. 5 AAAA 2600:9000:5302:e700:0:0:0:1
g-ns-1064.awsdns-37.org. 5 AAAA 2600:9000:5304:2800:0:0:0:1
g-ns-1637.awsdns-37.org. 5 AAAA 2600:9000:5306:6500:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0