Apex domains cannot have CNAME records.
Question and response
Question
dig rockislandwildflowers.com. NS
Answer
rockislandwildflowers.com. 5 NS ns-1747.awsdns-26.co.uk.
rockislandwildflowers.com. 5 NS ns-812.awsdns-37.net.
rockislandwildflowers.com. 5 NS ns-47.awsdns-05.com.
rockislandwildflowers.com. 5 NS ns-1692.awsdns-19.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0