Column DAX query

Hi,

Please check the below picture and the attached pbix file.

New Category CC =
SWITCH (
    TRUE (),
    Data[Category] = "Purchase", Data[Category],
    Data[Category] = "Service",
        Data[Category] & "_"
            & COUNTROWS (
                WINDOW (
                    1,
                    ABS,
                    0,
                    REL,
                    SUMMARIZE (
                        FILTER ( Data, Data[Category] = "Service" ),
                        Data[Product],
                        Data[Date]
                    ),
                    ORDERBY ( Data[Date], ASC ),
                    KEEP,
                    PARTITIONBY ( Data[Product] )
                )
            )
)