Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-55.org. NS
Answer
awsdns-55.org. 2 NS g-ns-1655.awsdns-55.org.
awsdns-55.org. 2 NS g-ns-1082.awsdns-55.org.
awsdns-55.org. 2 NS g-ns-183.awsdns-55.org.
awsdns-55.org. 2 NS g-ns-761.awsdns-55.org.
Authority
The response has no authority records.
Additional
g-ns-183.awsdns-55.org. 2 A 205.251.192.183
g-ns-761.awsdns-55.org. 2 A 205.251.194.249
g-ns-1082.awsdns-55.org. 2 A 205.251.196.58
g-ns-1655.awsdns-55.org. 2 A 205.251.198.119
g-ns-183.awsdns-55.org. 2 AAAA 2600:9000:5300:b700:0:0:0:1
g-ns-761.awsdns-55.org. 2 AAAA 2600:9000:5302:f900:0:0:0:1
g-ns-1082.awsdns-55.org. 2 AAAA 2600:9000:5304:3a00:0:0:0:1
g-ns-1655.awsdns-55.org. 2 AAAA 2600:9000:5306:7700:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0