Apex domains cannot have CNAME records.
Question and response
Question
dig rollernet.us. NS
Answer
rollernet.us. 5 NS ns1-i.rollernet.us.
rollernet.us. 5 NS ns3-i.rollernet.net.
rollernet.us. 5 NS ns2-i.rollernet.us.
Authority
The response has no authority records.
Additional
ns1-i.rollernet.us. 5 A 208.79.240.20
ns2-i.rollernet.us. 5 A 208.79.241.20
ns3-i.rollernet.net. 1 A 176.58.89.17
ns1-i.rollernet.us. 5 AAAA 2607:fe70:0:3:0:0:0:10
ns2-i.rollernet.us. 5 AAAA 2607:fe70:0:4:0:0:0:10
ns3-i.rollernet.net. 1 AAAA 2a00:dd80:3c:0:0:0:0:1e
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0