Apex domains cannot have CNAME records.
Question and response
Question
dig mkt296.com. NS
Answer
mkt296.com. 5 NS ns4.acoustic-adm.com.
mkt296.com. 5 NS ns2.acoustic-adm.com.
mkt296.com. 5 NS ns1.acoustic-adm.com.
mkt296.com. 5 NS ns3.acoustic-adm.com.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0