Apex domains cannot have CNAME records.
Question and response
Question
dig etop.pl. NS
Answer
etop.pl. 5 NS intruder.etop.pl.
etop.pl. 5 NS ivo.etop.pl.
Authority
The response has no authority records.
Additional
ivo.etop.pl. 5 A 80.72.32.6
intruder.etop.pl. 5 A 80.72.32.10
ivo.etop.pl. 5 AAAA 2a00:c90:0:0:0:0:0:70
intruder.etop.pl. 5 AAAA 2a00:c90:0:0:0:0:0:10
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0