Apex domains cannot have CNAME records.
Question and response
Question
dig idcfcloud.COM. NS
Answer
idcfcloud.com. 1 NS ns01.idc.jp.
idcfcloud.com. 1 NS ns03.idc.jp.
idcfcloud.com. 1 NS ns02.idc.jp.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0