Apex domains cannot have CNAME records.
Question and response
Question
dig co.ph. NS
Answer
co.ph. 5 NS ns1.commonmx.com.
co.ph. 5 NS ns2.commonmx.com.
Authority
The response has no authority records.
Additional
ns1.commonmx.com. 1 A 104.243.45.206
ns2.commonmx.com. 1 A 212.92.105.193
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0