Apex domains cannot have CNAME records.
Question and response
Question
dig vnslns.com. NS
Answer
vnslns.com. 3 NS pns32.cloudns.net.
vnslns.com. 3 NS pns34.cloudns.net.
vnslns.com. 3 NS pns31.cloudns.net.
vnslns.com. 3 NS pns33.cloudns.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0