Apex domains cannot have CNAME records.
Question and response
Question
dig planisys.net. NS
Answer
planisys.net. 4 NS dns2.planisys.net.
planisys.net. 4 NS dns4.planisys.net.
planisys.net. 4 NS dns6.planisys.net.
planisys.net. 4 NS dns3.planisys.net.
planisys.net. 4 NS inap-dns.planisys.net.
planisys.net. 4 NS dns1.planisys.net.
planisys.net. 4 NS dns5.planisys.io.
Authority
The response has no authority records.
Additional
dns1.planisys.net. 4 A 131.108.40.7
dns2.planisys.net. 4 A 179.63.251.216
dns3.planisys.net. 4 A 190.185.104.7
dns4.planisys.net. 4 A 179.63.248.7
dns5.planisys.io. 4 A 143.42.183.85
dns6.planisys.net. 4 A 154.57.159.147
dns1.planisys.net. 4 AAAA 2803:bc00:0:0:0:0:0:84
dns5.planisys.io. 4 AAAA 2600:3c03:0:0:f03c:93ff:fe99:49bd
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0