Apex domains cannot have CNAME records.
Question and response
Question
dig unwired.co.ke. NS
Answer
unwired.co.ke. 4 NS ns3.safaricombusiness.co.ke.
unwired.co.ke. 4 NS ns4.safaricombusiness.co.ke.
unwired.co.ke. 4 NS ns1.safaricombusiness.co.ke.
unwired.co.ke. 4 NS ns2.safaricombusiness.co.ke.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0