parameter duplicates in Report Builder for Paginated Reports.

Try this as your dataset2

EVALUATE 
SUMMARIZECOLUMNS(
    'Providers'[PhysicianOrganization],
    FILTER(
        'DateDim',
        'DateDim'[YearMonth] = @YearMonth
    )
)

If the duplication is due to multiple rows in the dataset having the same PhysicianOrganization value, consider adding a DISTINCT clause directly in the DAX query or in the SQL query that gets the data.
Ensure that the slicer displays only distinct values. You can modify the DAX query to return distinct PhysicianOrganization values. For example, you can wrap your SUMMARIZECOLUMNS function with the following DISTINCT function:

EVALUATE 
DISTINCT(
    SUMMARIZECOLUMNS(
        'DateDim'[YearMonth],
        'Providers'[PhysicianOrganization]
    )
)

hackcrr

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