Apex domains cannot have CNAME records.
Question and response
Question
dig relaix.net. NS
Answer
relaix.net. 5 NS ns2.relaix.net.
relaix.net. 5 NS ns1.relaix.net.
relaix.net. 5 NS ns3.relaix.net.
Authority
The response has no authority records.
Additional
ns1.relaix.net. 5 A 5.199.248.162
ns2.relaix.net. 5 A 212.44.167.107
ns3.relaix.net. 5 A 5.199.248.163
ns1.relaix.net. 5 AAAA 2a00:fe0:0:300:0:0:0:1
ns2.relaix.net. 5 AAAA 2a00:1978:1:2:0:0:0:200
ns3.relaix.net. 5 AAAA 2a00:fe0:0:300:0:0:0:2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0