Aggregate Running Total Monthly

Use the date from your calendar dimension table, not the prod fact table.

Hi, M_SBS_6 

To achieve a cumulative total by month, you can modify the measure to ensure that it matches the monthly context.
You might want to try the DAX expression below:

Run_total_Monthly = 
CALCULATE(
    SUM(prod[amt]),
    FILTER(
        ALLSELECTED(prod[date].[Month]),
        prod[date] <= MAX(prod[date])
    )
)

If it does not help, please provide more details with your desired output and pbix file without privacy information (or some sample data)

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Best Regards

Yongkang Hua

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