Apex domains cannot have CNAME records.
Question and response
Question
dig chinaasthmadata.org. NS
Answer
chinaasthmadata.org. 5 NS ns-1860.awsdns-40.co.uk.
chinaasthmadata.org. 5 NS ns-629.awsdns-14.net.
chinaasthmadata.org. 5 NS ns-448.awsdns-56.com.
chinaasthmadata.org. 5 NS ns-1295.awsdns-33.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0