Apex domains cannot have CNAME records.
Question and response
Question
dig eesti.ee. NS
Answer
eesti.ee. 5 NS ans1.aso.ee.
eesti.ee. 5 NS ans2.aso.ee.
eesti.ee. 5 NS sec1.rcode0.net.
eesti.ee. 5 NS sec2.rcode0.net.
Authority
The response has no authority records.
Additional
ans1.aso.ee. 5 A 195.80.103.202
ans2.aso.ee. 5 A 195.80.96.217
sec1.rcode0.net. 5 A 192.174.68.100
sec2.rcode0.net. 5 A 176.97.158.100
ans1.aso.ee. 5 AAAA 2a02:88:0:417:195:80:103:202
ans2.aso.ee. 5 AAAA 2a02:88:0:420:195:80:96:217
sec1.rcode0.net. 5 AAAA 2001:67c:1bc:0:0:0:0:100
sec2.rcode0.net. 5 AAAA 2001:67c:10b8:0:0:0:0:100
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0