Apex domains cannot have CNAME records.
Question and response
Question
dig co.za. NS
Answer
co.za. 4 NS ns2us.dns.business.
co.za. 4 NS ns.coza.net.za.
co.za. 4 NS ns5.dns.net.za.
co.za. 4 NS ns2.dns.net.za.
co.za. 4 NS coza1.dnsnode.net.
Authority
The response has no authority records.
Additional
ns.coza.net.za. 4 A 206.223.136.200
ns2.dns.net.za. 4 A 196.29.59.175
ns5.dns.net.za. 4 A 196.29.59.176
ns2us.dns.business. 4 A 147.135.106.236
ns.coza.net.za. 4 AAAA 2001:43f8:30:0:0:0:0:200
ns2.dns.net.za. 4 AAAA 2001:43f8:790:5901:0:0:c41d:3baf
ns5.dns.net.za. 4 AAAA 2001:43f8:790:5901:0:0:c41d:3bb0
ns2us.dns.business. 4 AAAA 2604:2dc0:200:2eb:0:0:0:2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0