Apex domains cannot have CNAME records.
Question and response
Question
dig prod-empresarial.com.mx. NS
Answer
prod-empresarial.com.mx. 3 NS nsmex2.uninet.net.mx.
prod-empresarial.com.mx. 3 NS nsgdl2.uninet.net.mx.
prod-empresarial.com.mx. 3 NS dnsadm-interno.uninet.net.mx.
prod-empresarial.com.mx. 3 NS nsmty2.uninet.net.mx.
Authority
The response has no authority records.
Additional
nsgdl2.uninet.net.mx. 2 A 200.23.242.204
nsmex2.uninet.net.mx. 2 A 200.33.146.204
nsmty2.uninet.net.mx. 2 A 200.33.148.205
nsgdl2.uninet.net.mx. 2 AAAA 2806:1030:ffff:1:0:0:0:1
nsmex2.uninet.net.mx. 2 AAAA 2806:1050:ffff:1:0:0:0:4
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0