Apex domains cannot have CNAME records.
Question and response
Question
dig sakurareform.net. NS
Answer
sakurareform.net. 5 NS ns-1347.awsdns-40.org.
sakurareform.net. 5 NS ns-1421.awsdns-49.org.
sakurareform.net. 5 NS ns-1990.awsdns-56.co.uk.
sakurareform.net. 5 NS ns-430.awsdns-53.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0