Apex domains cannot have CNAME records.
Question and response
Question
dig ipxon.net. NS
Answer
ipxon.net. 5 NS ns02.ipxon.net.
ipxon.net. 5 NS ns01.ipxon.net.
ipxon.net. 5 NS ns04.ipxon.net.
ipxon.net. 5 NS ns03.ipxon.net.
Authority
The response has no authority records.
Additional
ns01.ipxon.net. 5 A 190.103.178.245
ns02.ipxon.net. 5 A 190.103.176.245
ns03.ipxon.net. 5 A 138.186.141.245
ns04.ipxon.net. 5 A 138.186.143.245
ns01.ipxon.net. 5 AAAA 2800:ba0:10:a1:190:103:178:245
ns02.ipxon.net. 5 AAAA 2800:ba0:16:a1:190:103:176:245
ns03.ipxon.net. 5 AAAA 2800:ba0:8:a1:138:186:141:245
ns04.ipxon.net. 5 AAAA 2800:ba0:2:a1:138:186:143:245
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0