Apex domains cannot have CNAME records.
Question and response
Question
dig pflegedienst-johnson.com. NS
Answer
pflegedienst-johnson.com. 5 NS ns.pflegedienst-johnson.com.
Authority
The response has no authority records.
Additional
ns.pflegedienst-johnson.com. 5 A 80.153.35.177
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0