Apex domains cannot have CNAME records.
Question and response
Question
dig oficinasitecca.edu.do. NS
Answer
oficinasitecca.edu.do. 4 NS ns41.cloudns.net.
oficinasitecca.edu.do. 4 NS ns44.cloudns.net.
oficinasitecca.edu.do. 4 NS ns43.cloudns.net.
oficinasitecca.edu.do. 4 NS ns42.cloudns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0