demo.vtiger.com has no NS records.
NS records for this zone are defined at vtiger.com.
NS records for this zone are defined at vtiger.com.
Question and response
Question
dig demo.vtiger.com. NS
Answer
The response has no answer records.
Authority
vtiger.com. 1800 SOA chad.ns.cloudflare.com. dns.cloudflare.com. 2399060091 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0