mailin.pluspunkthosting.de has no CNAME records.
Question and response
Question
dig mailin.pluspunkthosting.de. NS
Answer
The response has no answer records.
Authority
pluspunkthosting.de. 3528 SOA nameserver1.pluspunkthosting.de. hostmaster.punkt.de. 2025041401 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0