antispam.da.net.tw has no NS records.
NS records for this zone are defined at da.net.tw.
NS records for this zone are defined at da.net.tw.
Question and response
Question
dig antispam.da.net.tw. NS
Answer
The response has no answer records.
Authority
da.net.tw. 1800 SOA aspen.ns.cloudflare.com. dns.cloudflare.com. 2396093390 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0