Apex domains cannot have CNAME records.
Question and response
Question
dig d365yontm7w8ma.cloudfront.net. NS
Answer
d365yontm7w8ma.cloudfront.net. 5 NS ns-77.awsdns-09.com.
d365yontm7w8ma.cloudfront.net. 5 NS ns-2033.awsdns-62.co.uk.
d365yontm7w8ma.cloudfront.net. 5 NS ns-1207.awsdns-22.org.
d365yontm7w8ma.cloudfront.net. 5 NS ns-794.awsdns-35.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0