Apex domains cannot have CNAME records.
Question and response
Question
dig sta.estpak.ee. NS
Answer
sta.estpak.ee. 5 NS ns9.elion.ee.
sta.estpak.ee. 5 NS ns8.elion.ee.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0