Apex domains cannot have CNAME records.
Question and response
Question
dig raiffeisen-esafe.at. NS
Answer
raiffeisen-esafe.at. 5 NS ns2.raiffeisen.at.
raiffeisen-esafe.at. 5 NS ns1.raiffeisen.at.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0