styx.kel.de.core.tng.de has no CNAME records.
Question and response
Question
dig styx.kel.de.core.tng.de. NS
Answer
The response has no answer records.
Authority
core.tng.de. 10800 SOA tng.de. hostmaster.tng.de. 2022101101 3600 1800 3600000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0