Apex domains cannot have CNAME records.
Question and response
Question
dig ecomputer.es. NS
Answer
ecomputer.es. 4 NS dns7.servidoresdns.net.
ecomputer.es. 4 NS dns8.servidoresdns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0