Apex domains cannot have CNAME records.
Question and response
Question
dig weebly.com. NS
Answer
weebly.com. 5 NS ns-646.awsdns-16.net.
weebly.com. 5 NS ns-123.awsdns-15.com.
weebly.com. 5 NS ns-1797.awsdns-32.co.uk.
weebly.com. 5 NS ns-1500.awsdns-59.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0