Apex domains cannot have CNAME records.
Question and response
Question
dig piedmontbroadband.com. NS
Answer
piedmontbroadband.com. 1 NS ns1.inmotionhosting.com.
piedmontbroadband.com. 1 NS ns2.inmotionhosting.com.
Authority
The response has no authority records.
Additional
ns2.inmotionhosting.com. 1 A 70.39.150.2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0