Apex domains cannot have CNAME records.
Question and response
Question
dig hostfactory.swiss. NS
Answer
hostfactory.swiss. 5 NS ns02.hostfactory.ch.
hostfactory.swiss. 5 NS ns01.hostfactory.ch.
Authority
The response has no authority records.
Additional
ns01.hostfactory.ch. 5 A 185.117.168.140
ns02.hostfactory.ch. 5 A 156.67.10.18
ns01.hostfactory.ch. 5 AAAA 2a0e:f0c0:1:13:c:0:0:10
ns02.hostfactory.ch. 5 AAAA 2a03:da41:d:0:0:0:0:11
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0