Apex domains cannot have CNAME records.
Question and response
Question
dig eww.at. NS
Answer
eww.at. 5 NS dns5.itandtel.at.
eww.at. 5 NS dns3.itandtel.at.
eww.at. 5 NS dns4.itandtel.at.
eww.at. 5 NS dns6.itandtel.at.
Authority
The response has no authority records.
Additional
dns3.itandtel.at. 5 A 85.31.14.251
dns4.itandtel.at. 5 A 194.112.251.4
dns5.itandtel.at. 5 A 192.174.68.100
dns6.itandtel.at. 5 A 176.97.158.100
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0