Apex domains cannot have CNAME records.
Question and response
Question
dig famedly.de. NS
Answer
famedly.de. 5 NS ns0.famedly.de.
famedly.de. 5 NS ns1.famedly.de.
Authority
The response has no authority records.
Additional
ns0.famedly.de. 5 A 157.90.18.210
ns1.famedly.de. 5 A 51.159.187.13
ns0.famedly.de. 5 AAAA 2a01:4f8:1c1c:6b2e:0:0:0:1
ns1.famedly.de. 5 AAAA 2001:bc8:1210:46ff:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0