Apex domains cannot have CNAME records.
Question and response
Question
dig design-b2b.com. NS
Answer
design-b2b.com. 5 NS ns1.design-b2b.com.
Authority
The response has no authority records.
Additional
ns1.design-b2b.com. 5 A 178.57.220.192
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0