smtp2.nethys.be has no MX records.
Question and response
Question
dig smtp2.nethys.be. MX
Answer
The response has no answer records.
Authority
nethys.be. 60 SOA ns1.register.be. info.register.be. 1770621104 7200 3600 604800 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0