Hi @kiko, this is due to the cyclic nature of the data, please refer to this documentation. If that does not help, please create a sample dashboard with sample dataset showing your problem state using Arena and post it here. Details on using Arena can be found here - QuickSight Arena
Working with cyclical data
Sometimes, the data that you use for a Sankey diagram contains cycles. For example, suppose that you’re visualizing user traffic flows between pages on a website. You might discover that users who come to page A move to page E, and then come back to page A. An entire flow might look something like A-E-A-B-A-E-A.
When your data contains cycles, the nodes in each cycle are repeated in QuickSight. For example, if your data contains the flow A-E-A-B-A-E-A, the following Sankey diagram is created.
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