Apex domains cannot have CNAME records.
Question and response
Question
dig telcove.com. NS
Answer
telcove.com. 5 NS ns24.customer.level3.net.
telcove.com. 5 NS ns19.customer.level3.net.
telcove.com. 5 NS ns9.customer.level3.net.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0