Revenue Cloud Advanced: SalesTransaction Context Definition mapping from Quote Line Group to Quote Line does not populate target field

Follow these steps in order. The custom attribute must be added on the SalesTransactionItem node and mapped through QuoteEntitiesMapping; you cannot map a Quote Line Group field directly into a Quote Line field outside this pattern.

Cause 1: Custom attribute is missing from the SalesTransactionItem node
1. Navigate to Setup > Object Manager > Quote Line [QuoteLineItem] and confirm the target field exists with the exact API name you intend to populate (for example a custom Location [Location__c] text field, or use the standard Item Description [ItemDescription] field).
2. If you are sourcing from a custom Quote Line Group field, navigate to Setup > Object Manager > Quote Line Group [QuoteLineGroup] and confirm the source field exists with the API name you intend to read.
3. From Setup, in the Quick Find box, enter Context Definitions and select Context Definitions.
4. Locate the SalesTransactionContext [SalesTransactionContext__stdctx] record. Click the row menu and select Extend if you do not yet have a custom definition; otherwise open your existing extended definition.
5. Enter a Name for your custom context definition (for example MyOrgSalesTransactionContext) and click Next, then Save.
6. Open the new custom definition. On the Custom Definitions tab, click Edit.
7. Under the SalesTransactionItem node, click Add Attribute and create the attribute that will carry the value into the Quote Line. Set Type = INPUT OUTPUT and Data Type = STRING for text fields (or NUMBER for numeric fields). For a location example, name the attribute Location [Location__c]. Save your changes.

Cause 2: Mapping is not configured under QuoteEntitiesMapping or is not marked as default
1. Open your custom context definition and select the Map Data tab.
2. For the QuoteEntitiesMapping row, click the row menu and select Edit SObject Mapping.
3. Select the Mark as Default checkbox and click Map. The Context Mapping builder opens.
4. On the left (Structure), select the attribute you created on the SalesTransactionItem node (for example Location [Location__c]).
5. On the right (Connect Objects), select the QuoteLineItem sObject lookup, then drill into the Quote Line Group [SBQQ__Group__r or QuoteLineGroup] relationship and select the source field (for example Group Name [GroupName] or your custom group field). The mapping line draws between the two items.
6. To populate the standard Item Description [ItemDescription] field on the Quote Line, select ItemDescription as the target attribute on the SalesTransactionItem node and connect it to QuoteLineGroup.GroupName via the QuoteLineItem sObject lookup.
7. Click Save to persist the mapping.

Cause 3: Context definition is not activated
1. Return to Setup > Context Definitions and open your custom definition.
2. From the Custom Definitions tab row menu, select Activate. The Status changes to Active.
3. If you also need this definition used at runtime by the SalesTransaction node, navigate to Setup > Context Definition Settings, and from the Sales Transaction Context Definition header select your newly created context definition.
4. If the error "We couldn't fetch the context definition name and its associated mapping name from the Context Use Case Mapping object" appears, confirm the context definition is Active and that the QuoteEntitiesMapping is marked as default and saved; the error is raised when no active default Context Use Case Mapping exists for the selected SalesTransaction Context Definition.

Cause 4: Attribute defined at the wrong node level
1. If you placed the attribute on the SalesTransaction (root) node instead of the SalesTransactionItem node, delete it and recreate it under SalesTransactionItem. Quote Line Item-level fields can only be populated from attributes defined on the SalesTransactionItem node.

Confirm the issue is resolved by opening a test Quote, adding a Quote Line Group with a populated source field (for example GroupName), adding a Quote Line Item under that group, clicking Calculate, and verifying that the target Quote Line field (for example Item Description [ItemDescription] or your custom Location [Location__c] field) now displays the value from the Quote Line Group.