Apex domains cannot have CNAME records.
Question and response
Question
dig srv02.h4hosting.eu. NS
Answer
srv02.h4hosting.eu. 5 NS ns2.h4hosting.eu.
srv02.h4hosting.eu. 5 NS ns1.h4hosting.eu.
Authority
The response has no authority records.
Additional
ns1.h4hosting.eu. 5 A 178.217.81.67
ns2.h4hosting.eu. 5 A 178.217.83.3
ns1.h4hosting.eu. 5 AAAA 2a01:5cc0:1:5:0:0:0:3a5
ns2.h4hosting.eu. 5 AAAA 2a01:5cc0:1:3:0:0:0:3
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0