Apex domains cannot have CNAME records.
Question and response
Question
dig zyvantiro.org. NS
Answer
zyvantiro.org. 5 NS ns-1756.awsdns-27.co.uk.
zyvantiro.org. 5 NS ns-1059.awsdns-04.org.
zyvantiro.org. 5 NS ns-1327.awsdns-37.org.
zyvantiro.org. 5 NS ns-1937.awsdns-50.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0