Apex domains cannot have CNAME records.
Question and response
Question
dig UMKAONLINE.RU. NS
Answer
UMKAONLINE.RU. 2 NS ns2.UMKAONLINE.RU.
UMKAONLINE.RU. 2 NS ns1.UMKAONLINE.RU.
Authority
The response has no authority records.
Additional
ns1.umkaonline.ru. 2 A 134.19.151.186
ns2.umkaonline.ru. 2 A 134.19.151.187
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0