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