Apex domains cannot have CNAME records.
Question and response
Question
dig salaamtakaful.com. NS
Answer
salaamtakaful.com. 5 NS ns.cyber.net.pk.
salaamtakaful.com. 5 NS ns1.cyber.net.pk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0