Apex domains cannot have CNAME records.
Question and response
Question
dig brujula.net. NS
Answer
brujula.net. 5 NS dns.brujula.net.
brujula.net. 5 NS dns3.brujula.net.
brujula.net. 5 NS dns2.brujula.net.
brujula.net. 5 NS dns1.globalgate.com.ar.
Authority
The response has no authority records.
Additional
dns.brujula.net. 5 A 104.236.158.117
dns1.globalgate.com.ar. 5 A 200.0.185.100
dns2.brujula.net. 5 A 104.131.74.119
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0