Apex domains cannot have CNAME records.
Question and response
Question
dig vornetixa.com. NS
Answer
vornetixa.com. 5 NS ns-457.awsdns-57.com.
vornetixa.com. 5 NS ns-771.awsdns-32.net.
vornetixa.com. 5 NS ns-1690.awsdns-19.co.uk.
vornetixa.com. 5 NS ns-1975.awsdns-54.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0