Apex domains cannot have CNAME records.
Question and response
Question
dig alessiagrandi.com. NS
Answer
alessiagrandi.com. 5 NS ns-680.awsdns-21.net.
alessiagrandi.com. 5 NS ns-514.awsdns-00.net.
alessiagrandi.com. 5 NS ns-169.awsdns-21.com.
alessiagrandi.com. 5 NS ns-1525.awsdns-62.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0