Apex domains cannot have CNAME records.
Question and response
Question
dig opusinteractive.com. NS
Answer
opusinteractive.com. 3 NS ns3.opustertiary.com.
opusinteractive.com. 3 NS ns2.opusinteractive.io.
opusinteractive.com. 3 NS ns1.opusinteractive.io.
Authority
The response has no authority records.
Additional
ns1.opusinteractive.io. 3 A 216.151.4.2
ns2.opusinteractive.io. 4 A 205.235.95.100
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0