Apex domains cannot have CNAME records.
Question and response
Question
dig pimefactura.com. NS
Answer
pimefactura.com. 5 NS dns50.servidoresdns.net.
pimefactura.com. 5 NS dns49.servidoresdns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0