mx3.besserwisser.org has no CNAME records.
Question and response
Question
dig mx3.besserwisser.org. NS
Answer
The response has no answer records.
Authority
besserwisser.org. 300 SOA primary.se. mansaxel.machina.se. 2026022601 301 3600 3600000 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0