Apex domains cannot have CNAME records.
Question and response
Question
dig herbette.org. NS
Answer
herbette.org. 5 NS ns-749.awsdns-29.net.
herbette.org. 5 NS ns-1879.awsdns-42.co.uk.
herbette.org. 5 NS ns-1901.awsdns-45.co.uk.
herbette.org. 5 NS ns-1992.awsdns-57.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0