Apex domains cannot have CNAME records.
Question and response
Question
dig tourism.uzaig.uz. NS
Answer
tourism.uzaig.uz. 5 NS ns1.tourism.uzaig.uz.
tourism.uzaig.uz. 5 NS ns2.tourism.uzaig.uz.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0