The TPE blocks mapping sources contained from within a Loop shape to activities that are mapped to items that are outside of the loop.
Looping activities refers to actions that loop, or repeat, within an orchestration. It is possible to capture the events from actions that loop within an orchestration. To do this, you create another activity and map all of the new activity milestones and data inside the loop. This is necessary because the data processing in the loop will occur more than once per scheduled execution.
For example, if you have a purchase order with multiple line items that process in a loop, questions like “Which purchase orders have item prices of $100?" are ambiguous. Unambiguous questions are:
Which purchase orders have line items with a price of $100?
Which purchase orders have Total/Min/Max item prices of $100?
Creating unambiguous questions requires thinking of the line items as something separate from the purchase order. In the Tracking Profile Editor, the root activity (for example, a purchase order) maps to all actions outside the loop. The child activity (for example, a line item) maps to the actions inside the loop.
The typical approach to working with these types of constructs is to decompose the repeating loop and to have a related activity based on the inner activity that is related to the outer activity.
You need to use a payload item as the ActivityID for the root activity and have this payload item available in some of the messages inside the loop. Map the activity to the relationship node that displays under the child activity and name it as the root activity.