Apex domains cannot have CNAME records.
Question and response
Question
dig rastreator.com. NS
Answer
rastreator.com. 4 NS dns24.servidoresdns.net.
rastreator.com. 4 NS dns23.servidoresdns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0