Apex domains cannot have CNAME records.
Question and response
Question
dig enspirion.pl. NS
Answer
enspirion.pl. 5 NS dns2.tld.pl.
enspirion.pl. 5 NS dns1.tld.pl.
enspirion.pl. 5 NS dns3.tld.pl.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0