Apex domains cannot have CNAME records.
Question and response
Question
dig nefos.cloud. NS
Answer
nefos.cloud. 5 NS ns2.as202591.net.
nefos.cloud. 5 NS ns3.as202591.net.
nefos.cloud. 5 NS ns4.as202591.net.
Authority
The response has no authority records.
Additional
ns2.as202591.net. 5 A 185.150.186.25
ns3.as202591.net. 5 A 92.119.28.26
ns4.as202591.net. 5 A 45.154.164.23
ns2.as202591.net. 5 AAAA 2a07:7280:0:186:f816:3eff:fe9d:ef98
ns3.as202591.net. 5 AAAA 2a09:b340:0:0:f816:3eff:fe72:f218
ns4.as202591.net. 5 AAAA 2a0f:bd00:0:0:f816:3eff:feb2:a28a
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0