mail.systemhaus.net has no MX records.
Question and response
Question
dig mail.systemhaus.net. MX
Answer
The response has no answer records.
Authority
systemhaus.net. 3600 SOA ns01.systemhaus.net. dnsadmin.systemhaus.net. 2025082601 720 1800 3600 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0