Apex domains cannot have CNAME records.
Question and response
Question
dig revistacult.com.br. NS
Answer
revistacult.com.br. 4 NS d.sec.dns.br.
revistacult.com.br. 4 NS e.sec.dns.br.
Authority
The response has no authority records.
Additional
e.sec.dns.br. 2 A 200.192.232.14
e.sec.dns.br. 2 AAAA 2001:12f8:b:1:0:0:0:14
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0