Apex domains cannot have CNAME records.
Question and response
Question
dig dy9bfhf62qri8.cloudfront.net. NS
Answer
dy9bfhf62qri8.cloudfront.net. 5 NS ns-1007.awsdns-61.net.
dy9bfhf62qri8.cloudfront.net. 5 NS ns-1158.awsdns-16.org.
dy9bfhf62qri8.cloudfront.net. 5 NS ns-1805.awsdns-33.co.uk.
dy9bfhf62qri8.cloudfront.net. 5 NS ns-193.awsdns-24.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0