Apex domains cannot have CNAME records.
Question and response
Question
dig dotslash.co.za. NS
Answer
dotslash.co.za. 5 NS ns4-07.azure-dns.info.
dotslash.co.za. 5 NS ns2-07.azure-dns.net.
dotslash.co.za. 5 NS ns1-07.azure-dns.com.
dotslash.co.za. 5 NS ns3-07.azure-dns.org.
Authority
The response has no authority records.
Additional
ns1-07.azure-dns.com. 2 A 13.107.236.7
ns2-07.azure-dns.net. 2 A 150.171.21.7
ns3-07.azure-dns.org. 2 A 204.14.183.7
ns4-07.azure-dns.info. 2 A 208.84.5.7
ns1-07.azure-dns.com. 2 AAAA 2603:1061:0:700:0:0:0:7
ns2-07.azure-dns.net. 2 AAAA 2620:1ec:8ec:700:0:0:0:7
ns3-07.azure-dns.org. 2 AAAA 2a01:111:4000:700:0:0:0:7
ns4-07.azure-dns.info. 2 AAAA 2620:1ec:bda:700:0:0:0:7
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0