A FlexCard displays data by binding its elements to a data source, typically the JSON output from a DataRaptor. For a field to display a value, the Field property of the element on the FlexCard canvas must exactly match the corresponding key (JSON path name) in the data source's output JSON. If there is a mismatch for a single field (e.g., the DataRaptor outputs AcctName but the FlexCard element is mapped to AccountName), the FlexCard cannot locate the data for that specific element. As a result, only the element's label will be rendered, while other correctly mapped fields will display their data successfully.

1. Salesforce Help

OmniStudio Documentation

"Display Data on a FlexCard": This document explains the process of data binding. It specifies that to display data

you must drag a field element onto the canvas and in the properties

set the Field attribute to the name of the JSON node from the data source. This directly supports the conclusion that a name mismatch causes the display failure. (See section: Add Fields and Actions to a State).

2. Salesforce Trailhead

"OmniStudio FlexCards" Module

"Bind Data to a FlexCard" Unit: This module provides practical examples demonstrating that the Field property of a FlexCard element must be mapped to the exact name of the key in the JSON data structure provided by the DataRaptor. A failure to match these names results in the exact behavior described in the question.

3. Salesforce Help

OmniStudio Documentation

"FlexCard Data Source Properties": This resource details how data sources are configured. It shows that the Data Source Input Map (using {recordId}) provides context for the entire data retrieval operation. An error here

as suggested in option A

would impact the whole data set. (See section: Context Variables).