Apex domains cannot have CNAME records.
Question and response
Question
dig skorpionet.com.br. NS
Answer
skorpionet.com.br. 1 NS dns2.skorpionet.com.br.
skorpionet.com.br. 1 NS dns1.skorpionet.com.br.
Authority
The response has no authority records.
Additional
dns1.skorpionet.com.br. 1 A 177.124.88.18
dns2.skorpionet.com.br. 1 A 177.124.88.19
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0