ns.vistec.net has no CNAME records.
Question and response
Question
dig ns.vistec.net. NS
Answer
The response has no answer records.
Authority
vistec.net. 74 SOA ns.vistec.com. root.ns.vistec.com. 2026020401 7200 7200 1209600 120
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0