Apex domains cannot have CNAME records.
Question and response
Question
dig vorverstaerker.com. NS
Answer
vorverstaerker.com. 5 NS ns1.vorverstaerker.com.
vorverstaerker.com. 5 NS ns2.vorverstaerker.com.
Authority
The response has no authority records.
Additional
ns1.vorverstaerker.com. 5 A 72.9.157.212
ns2.vorverstaerker.com. 5 A 23.95.185.115
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0