Apex domains cannot have CNAME records.
Question and response
Question
dig saluduniversal.net.do. NS
Answer
saluduniversal.net.do. 4 NS ns2.claro.net.do.
saluduniversal.net.do. 4 NS ns1.claro.net.do.
Authority
The response has no authority records.
Additional
ns1.claro.net.do. 4 A 196.3.81.121
ns2.claro.net.do. 4 A 200.88.127.27
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0