Mapping between 2 table with Many to many relationship in POWERBI

Hi ngocnguyen ,

I created a sample pbix file(see the attachment), please check if that is what you want. You can create two measures as below to get it:

NRun date = 
VAR _dealer =
    SELECTEDVALUE ( 'Table 1'[Dealer] )
VAR _postdate =
    SELECTEDVALUE ( 'Table 1'[Post date] )
VAR _prepdate =
    CALCULATE (
        MAX ( 'Table 1'[Post date] ),
        FILTER ( ALLSELECTED ( 'Table 1' ), 'Table 1'[Dealer]=_dealer&&'Table 1'[Post date] <_postdate )
    )
RETURN
    CALCULATE (
        MIN ( 'Table 2'[Run date] ),
        FILTER (
            'Table 2',
            'Table 2'[Run date] < _postdate
                && 'Table 2'[Run date] > _prepdate
        )
    )

NAmount = 
CALCULATE (
    SUM ( 'Table 2'[Amount] ),
    FILTER ( 'Table 2', 'Table 2'[Run date] = [NRun date] )
)

Best Regards