Apex domains cannot have CNAME records.
Question and response
Question
dig limes.com.pl. NS
Answer
limes.com.pl. 5 NS jupiter.limes.com.pl.
limes.com.pl. 5 NS kalipso.limes.com.pl.
Authority
The response has no authority records.
Additional
jupiter.limes.com.pl. 5 A 193.110.228.33
kalipso.limes.com.pl. 5 A 193.110.228.10
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0