vmi571191.contaboserver.net has no CNAME records.
Question and response
Question
dig vmi571191.contaboserver.net. NS
Answer
The response has no answer records.
Authority
contaboserver.net. 2848 SOA ns1.contabo.net. hostmaster.contabo.de. 1771723878 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0