Apex domains cannot have CNAME records.
Question and response
Question
dig disesa.edu.do. NS
Answer
disesa.edu.do. 4 NS ns71.dnns.net.
disesa.edu.do. 4 NS ns70.dnns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0