mx-01.lis.eu has no MX records.
Question and response
Question
dig mx-01.lis.eu. MX
Answer
The response has no answer records.
Authority
lis.eu. 43200 SOA rz-ns-01.winsped.de. administrator.lis.eu. 2020122492 21600 21600 864000 43200
Additional
. 0 OPT ; payload 4000, xrcode 0, version 0, flags 0