Apex domains cannot have CNAME records.
Question and response
Question
dig zimet.net. NS
Answer
zimet.net. 5 NS ns1.bitterrootwood.com.
zimet.net. 5 NS ns2.bitterrootwood.com.
Authority
The response has no authority records.
Additional
ns1.bitterrootwood.com. 5 A 2.58.203.197
ns2.bitterrootwood.com. 5 A 2.58.203.197
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0