Apex domains cannot have CNAME records.
Question and response
Question
dig s3-deprecated.us-east-2.amazonaws.com. NS
Answer
s3-deprecated.us-east-2.amazonaws.com. 5 NS ns-1688.awsdns-19.co.uk.
s3-deprecated.us-east-2.amazonaws.com. 5 NS ns-260.awsdns-32.com.
s3-deprecated.us-east-2.amazonaws.com. 5 NS ns-878.awsdns-45.net.
s3-deprecated.us-east-2.amazonaws.com. 5 NS ns-1105.awsdns-10.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0