Apex domains cannot have CNAME records.
Question and response
Question
dig webankieta.pl. NS
Answer
webankieta.pl. 5 NS amit.ns.cloudflare.com.
webankieta.pl. 5 NS sara.ns.cloudflare.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0