realm_id_not_event_derived· reason_code· applies to event_envelopeSub-reason for schema_violation when ak.realm.create carries a forbidden envelope realm_id instead of the realm_genesis shape, when a Collaboration Realm does not retype the full 33-byte create Event token, when a Principal Control Realm does not match the 0x11 subject transcript, or when payload.object still carries an id field. See zh/models/realm-and-space.md section 2.5.