dns.wolfnet.pl has no CNAME records.
Question and response
Question
dig dns.wolfnet.pl. NS
Answer
The response has no answer records.
Authority
wolfnet.pl. 10329 SOA dns.wolfnet.pl. dns.wolfnet.pl. 2025121301 14400 900 2592000 604800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0