ns1.contabo.net has no CNAME records.
Question and response
Question
dig ns1.contabo.net. NS
Answer
The response has no answer records.
Authority
contabo.net. 3600 SOA ns1.contabo.net. hostmaster.contabo.de. 1772865077 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0