Apex domains cannot have CNAME records.
Question and response
Question
dig thesauri.edu.do. NS
Answer
thesauri.edu.do. 5 NS ns-185.awsdns-23.com.
thesauri.edu.do. 5 NS ns-1051.awsdns-03.org.
thesauri.edu.do. 5 NS ns-657.awsdns-18.net.
thesauri.edu.do. 5 NS ns-1848.awsdns-39.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0