In Manage Billing Documents app, the one-time customer name maintained in billing index doesn't get reflected under the field 'Sold-to Party' or 'Payer', instead, the name maintained in customer master data is displayed.
SAP S/4HANA Cloud
In Manage Billing Documents app, partnership related information is fetched by CDS view C_BillingDocument_F0797. In this view, the sold-to party value actually reads from field KNA1-NAME1, which is supposed to be maintained in customer master data at customer master level, versus document level.
This is by design that partnership name in billing index in Manage Billing Documents app get fetched from customer master data.
Under the circumstance of one-time customer, please always execute an extra step to go into the SD document to check the detailed customer name.
CPD, one-time customer, F0797, billing index , KBA , SD-FIO-BIL , Fiori UIs for Billing , Problem