Apex domains cannot have CNAME records.
Question and response
Question
dig vas-hosting.com. NS
Answer
vas-hosting.com. 5 NS ns.vas-hosting.com.
vas-hosting.com. 5 NS ns.vas-hosting.cz.
vas-hosting.com. 5 NS ns.vas-hosting.eu.
Authority
The response has no authority records.
Additional
ns.vas-hosting.cz. 5 A 95.168.209.105
ns.vas-hosting.eu. 5 A 83.167.224.189
ns.vas-hosting.com. 5 A 78.47.104.13
ns.vas-hosting.eu. 5 AAAA 2a01:430:100:57:0:0:0:25
ns.vas-hosting.com. 5 AAAA 2a01:4f8:c0c:1fbf:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0