Apex domains cannot have CNAME records.
Question and response
Question
dig casadosprodutosonline.com. NS
Answer
casadosprodutosonline.com. 5 NS ns2.casadosprodutosonline.com.
casadosprodutosonline.com. 5 NS ns1.casadosprodutosonline.com.
Authority
The response has no authority records.
Additional
ns1.casadosprodutosonline.com. 5 A 51.254.149.159
ns2.casadosprodutosonline.com. 5 A 23.19.74.166
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0