Apex domains cannot have CNAME records.
Question and response
Question
dig web.plus. NS
Answer
web.plus. 5 NS premium2.ezydomain.com.
web.plus. 5 NS premium4.ezydomain.com.
web.plus. 5 NS premium1.ezydomain.com.
web.plus. 5 NS premium3.ezydomain.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0