Apex domains cannot have CNAME records.
Question and response
Question
dig titodominios.net. NS
Answer
titodominios.net. 2 NS ns22.titodominios.net.
titodominios.net. 2 NS ns23.titodominios.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0