Apex domains cannot have CNAME records.
Question and response
Question
dig ttcom.ru. NS
Answer
ttcom.ru. 5 NS ns2.ttcom.ru.
ttcom.ru. 5 NS ns1.ttcom.ru.
Authority
The response has no authority records.
Additional
ns1.ttcom.ru. 5 A 95.140.16.1
ns2.ttcom.ru. 5 A 95.140.17.1
ns1.ttcom.ru. 5 AAAA 2a00:6520:0:1:0:0:0:1
ns2.ttcom.ru. 5 AAAA 2a00:6520:0:2:0:0:0:2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0