Apex domains cannot have CNAME records.
Question and response
Question
dig cdb.ebox-solutions.com. NS
Answer
cdb.ebox-solutions.com. 5 NS ns1.ebox-solutions.com.
cdb.ebox-solutions.com. 5 NS ns2.ebox-solutions.com.
Authority
The response has no authority records.
Additional
ns1.ebox-solutions.com. 5 A 74.124.210.242
ns2.ebox-solutions.com. 5 A 70.39.150.2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0