Apex domains cannot have CNAME records.
Question and response
Question
dig polinadia.com. NS
Answer
polinadia.com. 5 NS ns-545.awsdns-04.net.
polinadia.com. 5 NS ns-374.awsdns-46.com.
polinadia.com. 5 NS ns-2016.awsdns-60.co.uk.
polinadia.com. 5 NS ns-1219.awsdns-24.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0