Apex domains cannot have CNAME records.
Question and response
Question
dig cielofarol.com.br. NS
Answer
cielofarol.com.br. 1 NS ns3gnv.name.com.
cielofarol.com.br. 1 NS ns1kpv.name.com.
cielofarol.com.br. 1 NS ns2fkr.name.com.
cielofarol.com.br. 1 NS ns4ghm.name.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0