Apex domains cannot have CNAME records.
Question and response
Question
dig eventmaker.at. NS
Answer
eventmaker.at. 5 NS ns-1447.awsdns-52.org.
eventmaker.at. 5 NS ns-1649.awsdns-14.co.uk.
eventmaker.at. 5 NS ns-167.awsdns-20.com.
eventmaker.at. 5 NS ns-590.awsdns-09.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0