Sounds like what you want to do is filter to the Top N prior to adding the Transaction Type detail.

If so, then consider the attached, where the following was performed:

- removed your table calc filter (table calc filters happen late, and you want an early filter)

- placed customer on the filter shelf, and on the Top tab, configured to use the parameter

- made the Month filter a context, so it happens prior to the Top N filter

- made both global filters (not necessary, but saved a few clicks)

- changed the parameter to a type in with All instead of List, so it works with the top filter dialog

If you are wondering why the table calc filter did not work, it is because your data sparse (not all potential dimension combinations exist in the data), and there is no simple way to turn on Data Densification for a stacked bar chart. If you need the late filtering from a table calc, then there are other others, but they are more involved, and if needed, please let me know know and I can detail that route as well.

You can set other other filters to happen prior to the Top N filter by making them Context filters. Notice in the packaged workbook, the filter on Month is a Context filter.

There may be other factors at play not covered in your comment, if you are getting unexpected results, please post an example workbook that represents your situation, and detail the results that you expect.