sbserver.kooper.se has no CNAME records.
Question and response
Question
dig sbserver.kooper.se. NS
Answer
The response has no answer records.
Authority
kooper.se. 3418 SOA ns1.kooper.se. hostmaster.kooper.se. 2025112401 300 60 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0