Trailing twelve month variable on computed field doesn't update with time slicer

[PowerBIprentice]

Dear Community, I am confronted with the following situation:

Context:

I want to create a graph that shows the evolution of my sales over the last 12 months (Trailing Twelve months - TTM) BUT where each month is already the sum of the last 12 months (Moving Annul Total - MAT). And I'd like this view to change according to a time slicer. For example, if I choose the month of May 23, I should see:

• The month of May 23', the sum of the months from May 22 to May 23.
• The month of April 23', the sum of april 22 to april 23.
• The month of March 23', the sum of march 22 to march 23.
• Etc... for a total of 12 months

Problem:

My problem is that the graph doesn't follow the time slicer at all. When I put a month in my slicer, the graph gives me a single value for the last 30 days, whereas I'd like to see the last 12 months.

This is what I've done:

• I created a value for the MAT of sales

Sales_MAT = CALCULATE(    

                            sum(Sales[Sales]),DATESINPERIOD('Date Dimension'[DateDimension],

MAX('Date Dimension'[DateDimension]),-12,MONTH) )

• I created a value allowing me to have the last 12 months

TTM_Total_Sales =

VAR CurrentDate = MAX('Date Dimension'[DateDimension])

VAR PreviousDate = DATE(YEAR(CurrentDate),MONTH(CurrentDate)-12,DAY(CurrentDate))

VAR Result =

CALCULATE(

        Sales[Sales_MAT],

        FILTER(

            ALL('Date Dimension'[DateDimension]),

           'Date Dimension'[DateDimension]>=PreviousDate && 'Date Dimension'[DateDimension]<=CurrentDate

        )

)

RETURN

Result

And I don't understand what else I need to do....

Already thank you for your help !

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