mail.complea-hosting.dk has no CNAME records.
Question and response
Question
dig mail.complea-hosting.dk. NS
Answer
The response has no answer records.
Authority
complea-hosting.dk. 3481 SOA ns1.complea-hosting.dk. hostmaster.complea-hosting.dk. 23644 900 600 86400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0