Apex domains cannot have CNAME records.
Question and response
Question
dig lessonly.com. NS
Answer
lessonly.com. 4 NS ns-189.awsdns-23.com.
lessonly.com. 4 NS ns-644.awsdns-16.net.
lessonly.com. 4 NS ns-1334.awsdns-38.org.
lessonly.com. 4 NS ns-1580.awsdns-05.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0