Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-48.org. NS
Answer
awsdns-48.org. 5 NS g-ns-176.awsdns-48.org.
awsdns-48.org. 5 NS g-ns-1075.awsdns-48.org.
awsdns-48.org. 5 NS g-ns-754.awsdns-48.org.
awsdns-48.org. 5 NS g-ns-1648.awsdns-48.org.
Authority
The response has no authority records.
Additional
g-ns-176.awsdns-48.org. 5 A 205.251.192.176
g-ns-754.awsdns-48.org. 5 A 205.251.194.242
g-ns-1075.awsdns-48.org. 5 A 205.251.196.51
g-ns-1648.awsdns-48.org. 5 A 205.251.198.112
g-ns-176.awsdns-48.org. 5 AAAA 2600:9000:5300:b000:0:0:0:1
g-ns-754.awsdns-48.org. 5 AAAA 2600:9000:5302:f200:0:0:0:1
g-ns-1075.awsdns-48.org. 5 AAAA 2600:9000:5304:3300:0:0:0:1
g-ns-1648.awsdns-48.org. 5 AAAA 2600:9000:5306:7000:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0