How to show distinct strings month to month

Hi you7777 

Can you please try below dax?

ChangedAppLabels =
VAR CurrentMonthLabels =
    SELECTCOLUMNS(
        FILTER(
            'Zylo Trending',
            'Zylo Trending'[DB Loading Date] = MAX('Zylo Trending'[DB Loading Date])
        ),
        "App Label", 'Zylo Trending'[App Label],
        "DB Loading Date", 'Zylo Trending'[DB Loading Date]
    )

VAR PreviousMonthLabels =
    SELECTCOLUMNS(
        FILTER(
            'Zylo Trending',
            'Zylo Trending'[DB Loading Date] = 
                EDATE(MAX('Zylo Trending'[DB Loading Date]), -1)
        ),
        "App Label", 'Zylo Trending'[App Label],
        "DB Loading Date", 'Zylo Trending'[DB Loading Date]
    )

VAR AddedLabels =
    EXCEPT(CurrentMonthLabels, PreviousMonthLabels)

VAR RemovedLabels =
    EXCEPT(PreviousMonthLabels, CurrentMonthLabels)

RETURN
    UNION(
        SELECTCOLUMNS(
            AddedLabels,
            "Change Type", "Added",
            "App Label", [App Label],
            "DB Loading Date", [DB Loading Date]
        ),
        SELECTCOLUMNS(
            RemovedLabels,
            "Change Type", "Removed",
            "App Label", [App Label],
            "DB Loading Date", [DB Loading Date]
        )
    )

 This revised query should correctly identify added or removed labels between snapshots.

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Kind Regards,
Poojara
Data Analyst | MSBI Developer | Power BI Consultant
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