Apex domains cannot have CNAME records.
Question and response
Question
dig desdelprobadorblog.es. NS
Answer
desdelprobadorblog.es. 5 NS jason.ns.cloudflare.com.
desdelprobadorblog.es. 5 NS pat.ns.cloudflare.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0