Apex domains cannot have CNAME records.
Question and response
Question
dig mwprem.net. NS
Answer
mwprem.net. 5 NS mwns2.customer.ne.jp.
mwprem.net. 5 NS mwns1.customer.ne.jp.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0