mx1.kommitt.de has no CNAME records.
Question and response
Question
dig mx1.kommitt.de. NS
Answer
The response has no answer records.
Authority
kommitt.de. 824 SOA dns0.kommitt.de. hostmaster.kommitt.de. 2026021101 36000 3600 2419200 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0