Apex domains cannot have CNAME records.
Question and response
Question
dig cartaoriachuelo.com.br. NS
Answer
cartaoriachuelo.com.br. 5 NS ns-485.awsdns-60.com.
cartaoriachuelo.com.br. 5 NS ns-1398.awsdns-46.org.
cartaoriachuelo.com.br. 5 NS ns-814.awsdns-37.net.
cartaoriachuelo.com.br. 5 NS ns-1634.awsdns-12.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0