Apex domains cannot have CNAME records.
Question and response
Question
dig epsl1.com. NS
Answer
epsl1.com. 5 NS a11-65.akam.net.
epsl1.com. 5 NS a8-64.akam.net.
epsl1.com. 5 NS a24-67.akam.net.
epsl1.com. 5 NS a9-65.akam.net.
epsl1.com. 5 NS a1-108.akam.net.
epsl1.com. 5 NS a16-66.akam.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0