mx2.saxobank.com has no NS records.
NS records for this zone are defined at saxobank.com.
NS records for this zone are defined at saxobank.com.
Question and response
Question
dig mx2.saxobank.com. NS
Answer
The response has no answer records.
Authority
saxobank.com. 86400 SOA edns4.ultradns.com. premiumdns.support.neustar. 2019053769 28800 7200 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0