Apex domains cannot have CNAME records.
Question and response
Question
dig longlinesvoice.com. NS
Answer
longlinesvoice.com. 4 NS ns1.longlines.com.
longlinesvoice.com. 4 NS ns2.longlines.com.
Authority
The response has no authority records.
Additional
ns1.longlines.com. 4 A 66.172.200.11
ns2.longlines.com. 4 A 66.172.201.11
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0