Apex domains cannot have CNAME records.
Question and response
Question
dig doubleservice.com. NS
Answer
doubleservice.com. 5 NS ns-41.awsdns-05.com.
doubleservice.com. 5 NS ns-765.awsdns-31.net.
doubleservice.com. 5 NS ns-1079.awsdns-06.org.
doubleservice.com. 5 NS ns-1840.awsdns-38.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0