mx01.netplace.com has no NS records.
NS records for this zone are defined at netplace.com.
NS records for this zone are defined at netplace.com.
Question and response
Question
dig mx01.netplace.com. NS
Answer
The response has no answer records.
Authority
netplace.com. 600 SOA dns0.noris.net. hostmaster.noris.net.netplace.com. 1771849624 86400 86400 2419200 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0