Apex domains cannot have CNAME records.
Question and response
Question
dig adobeaemcloud.com. NS
Answer
adobeaemcloud.com. 5 NS ns-1617.awsdns-10.co.uk.
adobeaemcloud.com. 5 NS ns-631.awsdns-14.net.
adobeaemcloud.com. 5 NS ns-84.awsdns-10.com.
adobeaemcloud.com. 5 NS ns-1457.awsdns-54.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0