Apex domains cannot have CNAME records.
Question and response
Question
dig ig-zp.pl. NS
Answer
ig-zp.pl. 5 NS ns2.ig-zp.pl.
ig-zp.pl. 5 NS ns1.ig-zp.pl.
Authority
The response has no authority records.
Additional
ns1.ig-zp.pl. 5 A 91.225.188.35
ns2.ig-zp.pl. 5 A 91.225.188.35
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0