Apex domains cannot have CNAME records.
Question and response
Question
dig connection-telecom.com. NS
Answer
connection-telecom.com. 5 NS ns-za-cpt.telviva.com.
connection-telecom.com. 5 NS ns-za-jnb.telviva.com.
connection-telecom.com. 5 NS ns-us-nwk.telviva.com.
Authority
The response has no authority records.
Additional
ns-us-nwk.telviva.com. 5 A 104.200.31.68
ns-za-cpt.telviva.com. 5 A 197.155.250.168
ns-za-jnb.telviva.com. 5 A 197.155.248.168
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0