dns1.telekom.de has no CNAME records.
Question and response
Question
dig dns1.telekom.de. NS
Answer
The response has no answer records.
Authority
telekom.de. 600 SOA dns1.telekom.de. dnsadmin.t-systems.com. 2019037935 10800 1800 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0