Apex domains cannot have CNAME records.
Question and response
Question
dig vixontra.com. NS
Answer
vixontra.com. 4 NS ns-1614.awsdns-09.co.uk.
vixontra.com. 4 NS ns-1791.awsdns-31.co.uk.
vixontra.com. 4 NS ns-1169.awsdns-18.org.
vixontra.com. 4 NS ns-1606.awsdns-08.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0