mail.askja.de has no CNAME records.
Question and response
Question
dig mail.askja.de. NS
Answer
The response has no answer records.
Authority
askja.de. 3600 SOA ns.askja.de. hostmaster.askja.de. 2025111802 21600 7200 2400000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0