Date problem with formula - LASTDATE

Hi,  nor303
The error message "PARAMETER IS NOT THE CORRECT TYPE" usually indicates that the function is receiving an argument of a type that it does not need.

In your case, the problem may be with the function. This function requires a string as an argument, but it doesn't seem to be a string. If it's already a date, you don't need to use it.
You can try to modify your DAX expression as follows:

Saldo Siste Måned = 
CALCULATE(
    SUM('Qlik AGH (2)'[Saldo lån/kreditter]),
    FILTER(
        'Qlik AGH (2)',
        'Qlik AGH (2)'[Periode] = MAX('Qlik AGH (2)'[Periode]) &&
        'Qlik AGH (2)'[LTV] = "LTV"
    )
)

I don't know what this [Saldo lån/kreditter] is, so I'll calculate it according to your existing column [Saldo ] above. I hope this will help you.

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Best Regards

Yongkang Hua

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