Apex domains cannot have CNAME records.
Question and response
Question
dig awsdns-49.com. NS
Answer
awsdns-49.com. 4 NS g-ns-625.awsdns-49.com.
awsdns-49.com. 4 NS g-ns-1777.awsdns-49.com.
awsdns-49.com. 4 NS g-ns-50.awsdns-49.com.
awsdns-49.com. 4 NS g-ns-1201.awsdns-49.com.
Authority
The response has no authority records.
Additional
g-ns-50.awsdns-49.com. 4 A 205.251.192.50
g-ns-625.awsdns-49.com. 4 A 205.251.194.113
g-ns-1201.awsdns-49.com. 4 A 205.251.196.177
g-ns-1777.awsdns-49.com. 4 A 205.251.198.241
g-ns-50.awsdns-49.com. 4 AAAA 2600:9000:5300:3200:0:0:0:1
g-ns-625.awsdns-49.com. 4 AAAA 2600:9000:5302:7100:0:0:0:1
g-ns-1201.awsdns-49.com. 4 AAAA 2600:9000:5304:b100:0:0:0:1
g-ns-1777.awsdns-49.com. 4 AAAA 2600:9000:5306:f100:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0