Apex domains cannot have CNAME records.
Question and response
Question
dig suthost.com. NS
Answer
suthost.com. 4 NS ns8.alidns.com.
suthost.com. 4 NS ns7.alidns.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0