Matrix complex slicers

Hi MoMrCrane ,
Based on the description of your post, you want the slicer to filter by salesperson and then show all customers associated with that salesperson as well as show all invoices and transaction records for those customers (even if those records are not directly associated with the salesperson), right?
Since we don't have specific data, we tried to help you with our own example data, you can check the pbix file we uploaded to see how we did it!

ShowAllCustomerTransactions = 
VAR SelectedCustomers = 
    CALCULATETABLE(
        VALUES(Customer[Customer]),
        FILTER(
            Invoices,
            Invoices[SalesPerson] IN VALUES(Salespersons[SalesPerson])
        )
    )
RETURN
CALCULATE(
    SUM(Transactions[AmountDue]),
    Transactions[Customer] IN SelectedCustomers

I hope my method is helpful to you, if you have further questions, you can provide some sample data so that we can better help you to solve the problem!

Hope it helps!

Best regards,
Community Support Team_ Tom Shen

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