Are you using Tableau prep ?
(2-6) Run the flow and here is the error message.
We do not use the 'File Paths' field in the second clean step.
(we just use "sales type" field in CF, and "sales type" is from "File Paths" in the first clean step. )
The workaround is to move the CF before aggregation step.
As per this --->gTableau Prep Output Error with message "not available after aggregation" it seems to be a bug.
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