Apex domains cannot have CNAME records.
Question and response
Question
dig farmacard.net.do. NS
Answer
farmacard.net.do. 4 NS ns2.tricom.net.
farmacard.net.do. 4 NS ns1.tricom.net.
farmacard.net.do. 4 NS ns3.tricom.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0