Apex domains cannot have CNAME records.
Question and response
Question
dig ingemuntwyler.com. NS
Answer
ingemuntwyler.com. 5 NS ns-1537.awsdns-00.co.uk.
ingemuntwyler.com. 5 NS ns-1009.awsdns-62.net.
ingemuntwyler.com. 5 NS ns-307.awsdns-38.com.
ingemuntwyler.com. 5 NS ns-598.awsdns-10.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0