Apex domains cannot have CNAME records.
Question and response
Question
dig controlpanel.si. NS
Answer
controlpanel.si. 5 NS ns4.freedns.si.
controlpanel.si. 5 NS ns3.freedns.si.
controlpanel.si. 5 NS ns1.freedns.si.
controlpanel.si. 5 NS ns2.freedns.si.
Authority
The response has no authority records.
Additional
ns1.freedns.si. 5 A 212.44.101.101
ns2.freedns.si. 5 A 178.218.162.218
ns3.freedns.si. 5 A 5.144.175.1
ns4.freedns.si. 5 A 212.44.118.42
ns1.freedns.si. 5 AAAA 2a02:ec:260c:9002:0:0:0:1
ns3.freedns.si. 5 AAAA 2001:4b7a:100:1:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0