Apex domains cannot have CNAME records.
Question and response
Question
dig myprepaidcenter.com. NS
Answer
myprepaidcenter.com. 5 NS ns-890.awsdns-47.net.
myprepaidcenter.com. 5 NS ns-293.awsdns-36.com.
myprepaidcenter.com. 5 NS ns-1540.awsdns-00.co.uk.
myprepaidcenter.com. 5 NS ns-1452.awsdns-53.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0