Apex domains cannot have CNAME records.
Question and response
Question
dig 4dynamic.net. NS
Answer
4dynamic.net. 5 NS ns-1736.awsdns-25.co.uk.
4dynamic.net. 5 NS ns-827.awsdns-39.net.
4dynamic.net. 5 NS ns-328.awsdns-41.com.
4dynamic.net. 5 NS ns-1235.awsdns-26.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0