Apex domains cannot have CNAME records.
Question and response
Question
dig abacusai-ip.net. NS
Answer
abacusai-ip.net. 5 NS ns-1188.awsdns-20.org.
abacusai-ip.net. 5 NS ns-295.awsdns-36.com.
abacusai-ip.net. 5 NS ns-547.awsdns-04.net.
abacusai-ip.net. 5 NS ns-1985.awsdns-56.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0