Apex domains cannot have CNAME records.
Question and response
Question
dig mail.kg. NS
Answer
mail.kg. 5 NS ns2.elcat.kg.
mail.kg. 5 NS ns1.elcat.kg.
Authority
The response has no authority records.
Additional
NS1.ELCAT.kg. 5 A 212.42.96.1
NS2.ELCAT.kg. 5 A 212.42.96.2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0