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