Apex domains cannot have CNAME records.
Question and response
Question
dig anx-cus.net. NS
Answer
anx-cus.net. 5 NS anexia.fourthns.systems.
anx-cus.net. 5 NS anexia.thirdns.de.
anx-cus.net. 5 NS anexia.secondns.at.
anx-cus.net. 5 NS anexia.firstns.cc.
anx-cus.net. 5 NS anexia.fifthns.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0