Apex domains cannot have CNAME records.
Question and response
Question
dig 0-255.92.250.186.in-addr.arpa. NS
Answer
0-255.92.250.186.in-addr.arpa. 5 NS ns01.odhserver.com.
0-255.92.250.186.in-addr.arpa. 5 NS ns02.odhserver.com.
Authority
The response has no authority records.
Additional
ns01.odhserver.com. 5 A 18.223.14.48
ns02.odhserver.com. 5 A 18.223.31.206
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0