Apex domains cannot have CNAME records.
Question and response
Question
dig ydim.com. NS
Answer
ydim.com. 4 NS ns4.ydim.com.
ydim.com. 4 NS ns3.ydim.com.
ydim.com. 4 NS rack02.ydim.com.
Authority
The response has no authority records.
Additional
ns3.ydim.com. 4 A 69.65.29.210
ns4.ydim.com. 4 A 69.65.34.34
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0