Apex domains cannot have CNAME records.
Question and response
Question
dig net-rosas.com.br. NS
Answer
net-rosas.com.br. 5 NS ns1.net-rosas.com.br.
net-rosas.com.br. 5 NS ns2.net-rosas.com.br.
Authority
The response has no authority records.
Additional
ns1.net-rosas.com.br. 5 A 189.124.16.234
ns2.net-rosas.com.br. 5 A 189.124.16.235
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0