Apex domains cannot have CNAME records.
Question and response
Question
dig ip.ahisp.co.za. NS
Answer
ip.ahisp.co.za. 2 NS rv.dns2.co.za.
ip.ahisp.co.za. 2 NS rv.dns1.co.za.
Authority
The response has no authority records.
Additional
rv.dns1.co.za. 2 A 169.1.1.69
rv.dns2.co.za. 2 A 154.0.174.200
rv.dns1.co.za. 2 AAAA 2c0f:f4c0:0:0:0:0:0:69
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0