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Setting the Correct Aggregator Source
You need to set the “Source Module” field of the aggregator to where the bundles are coming from. This is usually an iterator module, but can also be a search/list/repeater module, or even the trigger module.
For more information, please refer to the Make Academy.
Hope this helps! Let me know if there are any further questions or issues.
— @samliew
P.S.: Investing some effort into the Make Academy will save you lots of time and frustration using Make.