Apex domains cannot have CNAME records.
Question and response
Question
dig woop.host. NS
Answer
woop.host. 5 NS ns1.zonomi.com.
woop.host. 5 NS ns6.zonomi.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0