Apex domains cannot have CNAME records.
Question and response
Question
dig diginsite.com. NS
Answer
diginsite.com. 5 NS edns123.ultradns.org.
diginsite.com. 5 NS prdflb-gtm-qydc.diginsite.com.
diginsite.com. 5 NS edns123.ultradns.com.
diginsite.com. 5 NS edns123.ultradns.biz.
diginsite.com. 5 NS edns123.ultradns.net.
diginsite.com. 5 NS qalflb-gtm-lvdc.diginsite.com.
diginsite.com. 5 NS qalflb-gtm-qydc.diginsite.com.
diginsite.com. 5 NS prdflb-gtm-lvdc.diginsite.com.
diginsite.com. 5 NS prfflb-gtm-lvdc.diginsite.com.
diginsite.com. 5 NS prfflb-gtm-qydc.diginsite.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0