Apex domains cannot have CNAME records.
Question and response
Question
dig kustomvoodoo.com. NS
Answer
kustomvoodoo.com. 5 NS ns-124.awsdns-15.com.
kustomvoodoo.com. 5 NS ns-690.awsdns-22.net.
kustomvoodoo.com. 5 NS ns-1554.awsdns-02.co.uk.
kustomvoodoo.com. 5 NS ns-1923.awsdns-48.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0