Apex domains cannot have CNAME records.
Question and response
Question
dig broadcloudpbx.com. NS
Answer
broadcloudpbx.com. 5 NS ns2.as13445.net.
broadcloudpbx.com. 5 NS ns1.as13445.net.
Authority
The response has no authority records.
Additional
ns1.as13445.net. 5 A 66.163.52.1
ns2.as13445.net. 5 A 66.163.53.1
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0