Apex domains cannot have CNAME records.
Question and response
Question
dig ns2.ahost.uz. NS
Answer
ns2.ahost.uz. 5 NS ns1.ahost.uz.
ns2.ahost.uz. 5 NS ns2.ahost.uz.
Authority
The response has no authority records.
Additional
ns1.ahost.uz. 5 A 37.153.159.20
ns2.ahost.uz. 5 A 91.98.193.184
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0