service.cyso.net has no MX records.
Question and response
Question
dig service.cyso.net. MX
Answer
The response has no answer records.
Authority
service.cyso.net. 300 SOA ns1.cyso.nl. dnsadmin.cysonet.com. 1771459200 16384 2048 1048576 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0