Apex domains cannot have CNAME records.
Question and response
Question
dig asistenciauniversal.net.do. NS
Answer
asistenciauniversal.net.do. 5 NS dns4.midominio.do.
asistenciauniversal.net.do. 5 NS dns3.midominio.do.
asistenciauniversal.net.do. 5 NS dns1.midominio.do.
asistenciauniversal.net.do. 5 NS dns2.midominio.do.
Authority
The response has no authority records.
Additional
dns3.midominio.do. 3 A 162.251.82.118
dns3.midominio.do. 3 A 162.251.82.119
dns3.midominio.do. 3 A 162.251.82.246
dns3.midominio.do. 3 A 162.251.82.247
dns4.midominio.do. 3 A 162.251.82.124
dns4.midominio.do. 3 A 162.251.82.125
dns4.midominio.do. 3 A 162.251.82.252
dns4.midominio.do. 3 A 162.251.82.253
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0