Apex domains cannot have CNAME records.
Question and response
Question
dig eu-central-2.compute.amazonaws.com. NS
Answer
eu-central-2.compute.amazonaws.com. 5 NS ns-141.awsdns-17.com.
eu-central-2.compute.amazonaws.com. 5 NS ns-761.awsdns-31.net.
eu-central-2.compute.amazonaws.com. 5 NS ns-1177.awsdns-19.org.
eu-central-2.compute.amazonaws.com. 5 NS ns-2034.awsdns-62.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0