Apex domains cannot have CNAME records.
Question and response
Question
dig pinoydns.com. NS
Answer
pinoydns.com. 5 NS ns-422.awsdns-52.com.
pinoydns.com. 5 NS ns-497.awsdns-62.com.
pinoydns.com. 5 NS ns-518.awsdns-00.net.
pinoydns.com. 5 NS ns-545.awsdns-04.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0