Apex domains cannot have CNAME records.
Question and response
Question
dig captcolo.com. NS
Answer
captcolo.com. 5 NS ns-780.awsdns-33.net.
captcolo.com. 5 NS ns-1552.awsdns-02.co.uk.
captcolo.com. 5 NS ns-391.awsdns-48.com.
captcolo.com. 5 NS ns-1165.awsdns-17.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0