muc.internetx.de has no MX records.
Question and response
Question
dig muc.internetx.de. MX
Answer
The response has no answer records.
Authority
muc.internetx.de. 86400 SOA nsa.domain-robot.org. hostmaster.internetx.de. 2021092304 39940 7200 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0