Apex domains cannot have CNAME records.
Question and response
Question
dig 1-grid.COM. NS
Answer
1-grid.COM. 1 NS etta.ns.cloudflare.COM.
1-grid.COM. 1 NS ajay.ns.cloudflare.COM.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0