Apex domains cannot have CNAME records.
Question and response
Question
dig monit24.pl. NS
Answer
monit24.pl. 5 NS dns.kochany.pl.
monit24.pl. 5 NS dns.monit24.net.
monit24.pl. 5 NS dns.sysrq.pl.
Authority
The response has no authority records.
Additional
dns.sysrq.pl. 2 A 176.119.36.243
dns.kochany.pl. 5 A 193.200.66.183
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0