Apex domains cannot have CNAME records.
Question and response
Question
dig bufetejaviervidal.com. NS
Answer
bufetejaviervidal.com. 5 NS ns-918.awsdns-50.net.
bufetejaviervidal.com. 5 NS ns-1692.awsdns-19.co.uk.
bufetejaviervidal.com. 5 NS ns-1815.awsdns-34.co.uk.
bufetejaviervidal.com. 5 NS ns-347.awsdns-43.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0