ns3ac.portunity.eu has no CNAME records.
Question and response
Question
dig ns3ac.portunity.eu. NS
Answer
The response has no answer records.
Authority
portunity.eu. 360 SOA ns3ac.portunity.eu. hostmaster.portunity.de. 1710232110 10800 3600 3600000 360
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0