Apex domains cannot have CNAME records.
Question and response
Question
dig oxalide.com. NS
Answer
oxalide.com. 5 NS ns-641.awsdns-16.net.
oxalide.com. 5 NS ns-1432.awsdns-51.org.
oxalide.com. 5 NS ns-1654.awsdns-14.co.uk.
oxalide.com. 5 NS ns-277.awsdns-34.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0