gns2.mapfrebhd.com.do has no CNAME records.
Question and response
Question
dig gns2.mapfrebhd.com.do. NS
Answer
The response has no answer records.
Authority
mapfrebhd.com.do. 48 SOA gns1.mapfrebhd.com.do. hostmaster.mapfrebhd.com.do. 1334 900 600 86400 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0