ssl.mail2000.com.tw has no NS records.
NS records for this zone are defined at mail2000.com.tw.
NS records for this zone are defined at mail2000.com.tw.
Question and response
Question
dig ssl.mail2000.com.tw. NS
Answer
The response has no answer records.
Authority
mail2000.com.tw. 3600 SOA ns-183.awsdns-22.com. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0