Apex domains cannot have CNAME records.
Question and response
Question
dig supplyon.com. NS
Answer
supplyon.com. 5 NS ns5.cdnetdns.cn.
supplyon.com. 5 NS ns1.cdnetdns.net.
supplyon.com. 5 NS ns2.cdnetdns.net.
supplyon.com. 5 NS ns6.cdnetdns.cn.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0