Apex domains cannot have CNAME records.
Question and response
Question
dig me-alain-1.oci.oraclerealm26.com. NS
Answer
me-alain-1.oci.oraclerealm26.com. 5 NS ns6.p200.dns.me-alain-1.oci.oraclerealm26.com.
me-alain-1.oci.oraclerealm26.com. 5 NS ns3.p200.dns.me-alain-1.oci.oraclerealm26.com.
me-alain-1.oci.oraclerealm26.com. 5 NS ns1.p200.dns.me-alain-1.oci.oraclerealm26.com.
me-alain-1.oci.oraclerealm26.com. 5 NS ns2.p200.dns.me-alain-1.oci.oraclerealm26.com.
me-alain-1.oci.oraclerealm26.com. 5 NS ns4.p200.dns.me-alain-1.oci.oraclerealm26.com.
me-alain-1.oci.oraclerealm26.com. 5 NS ns5.p200.dns.me-alain-1.oci.oraclerealm26.com.
Authority
The response has no authority records.
Additional
ns1.p200.dns.me-alain-1.oci.oraclerealm26.com. 5 A 84.235.133.239
ns2.p200.dns.me-alain-1.oci.oraclerealm26.com. 5 A 84.235.149.148
ns3.p200.dns.me-alain-1.oci.oraclerealm26.com. 5 A 84.235.150.118
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0