Apex domains cannot have CNAME records.
Question and response
Question
dig lumos.net. NS
Answer
lumos.net. 5 NS ns1.lumos.net.
lumos.net. 5 NS ns2.lumos.net.
Authority
The response has no authority records.
Additional
ns1.lumos.net. 5 A 216.12.0.7
ns2.lumos.net. 5 A 209.145.84.130
ns1.lumos.net. 5 AAAA 2607:f1d8:5:100:0:0:0:1
ns2.lumos.net. 5 AAAA 2607:f1d8:5:200:0:0:0:1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0