Apex domains cannot have CNAME records.
Question and response
Question
dig xnet.uz. NS
Answer
xnet.uz. 4 NS ns1.sarkor.com.
xnet.uz. 4 NS ns2.sarkor.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0