Apex domains cannot have CNAME records.
Question and response
Question
dig hulux.mx. NS
Answer
hulux.mx. 5 NS ns45.domaincontrol.com.
hulux.mx. 5 NS ns46.domaincontrol.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0