p6.mail2000.com.tw has no NS records.
NS records for this zone are defined at com.tw.
NS records for this zone are defined at com.tw.
Question and response
Question
dig p6.mail2000.com.tw. NS
Answer
The response has no answer records.
Authority
mail2000.com.tw. 1232 SOA ns-183.awsdns-22.com. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0