Apex domains cannot have CNAME records.
Question and response
Question
dig ziply.com. NS
Answer
ziply.com. 5 NS ns2.as20055.net.
ziply.com. 5 NS ns6.as20055.net.
ziply.com. 5 NS ns1.as20055.net.
ziply.com. 5 NS ns5.as20055.net.
ziply.com. 5 NS ns3.as20055.net.
ziply.com. 5 NS ns4.as20055.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0