mx.mailprotect.be has no NS records.
NS records for this zone are defined at mailprotect.be.
NS records for this zone are defined at mailprotect.be.
Question and response
Question
dig mx.mailprotect.be. NS
Answer
The response has no answer records.
Authority
mailprotect.be. 3600 SOA ns3.combell.net. hostmaster.mailprotect.be. 1764581328 10800 3600 604800 40000
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0