Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-52.org. NS
Answer
awsdns-52.org. 5 NS g-ns-1079.awsdns-52.org.
awsdns-52.org. 5 NS g-ns-758.awsdns-52.org.
awsdns-52.org. 5 NS g-ns-180.awsdns-52.org.
awsdns-52.org. 5 NS g-ns-1652.awsdns-52.org.
Authority
The response has no authority records.
Additional
g-ns-180.awsdns-52.org. 5 A 205.251.192.180
g-ns-758.awsdns-52.org. 5 A 205.251.194.246
g-ns-1079.awsdns-52.org. 5 A 205.251.196.55
g-ns-1652.awsdns-52.org. 5 A 205.251.198.116
g-ns-180.awsdns-52.org. 5 AAAA 2600:9000:5300:b400:0:0:0:1
g-ns-758.awsdns-52.org. 5 AAAA 2600:9000:5302:f600:0:0:0:1
g-ns-1079.awsdns-52.org. 5 AAAA 2600:9000:5304:3700:0:0:0:1
g-ns-1652.awsdns-52.org. 5 AAAA 2600:9000:5306:7400:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0