Apex domains cannot have CNAME records.
Question and response
Question
dig zaventrix.com. NS
Answer
zaventrix.com. 5 NS ns-1468.awsdns-55.org.
zaventrix.com. 5 NS ns-1308.awsdns-35.org.
zaventrix.com. 5 NS ns-1042.awsdns-02.org.
zaventrix.com. 5 NS ns-1299.awsdns-34.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0