Apex domains cannot have CNAME records.
Question and response
Question
dig tiavision.co.za. NS
Answer
tiavision.co.za. 5 NS edward.ns.cloudflare.com.
tiavision.co.za. 5 NS edna.ns.cloudflare.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0