error on retrieving data from sharepoint lists using a form in power app

Hi kbhalll 
Thank you for reaching out to the Microsoft Fabric community forum.

This error occurs because using LookUp() within ForAll() creates an invalid filter query when Power Apps communicates with SharePoint. The issue is typically caused by ambiguous column references or mismatched data types, leading to the "Possible invalid string in filter query" warning.

To avoid this, it's better to use AddColumns() to pull in related data from the second list. This method reduces ambiguity, enhances performance, and eliminates filter query errors.

For example:

Clear(colKPIInput);

ClearCollect(
    colKPIInput,
    AddColumns(
        Filter(
            Master_KPIs,
            Region = ddFilterregion.Selected.Value &&
            Process = ddFilterprocess.Selected.Value
        ),
        "MonthlyRecord",
        LookUp(
            'KPI_Monthly_data',
            KPI_id = Master_KPIs[@KPI_id] &&
            Month = ddFilterMonth.Selected.Value
        ),
        "InputNumerator", MonthlyRecord.Numerator,
        "InputDenominator", MonthlyRecord.Denominator,
        "InputComments", MonthlyRecord.Comments,
        "CalculatedSLA", MonthlyRecord.SLA_Percentage,
        "MonthlyDataRecordID", MonthlyRecord.ID,
        "IsEditMode", !IsBlank(MonthlyRecord)
    )
);

Set(varDataLoaded, true);

If you have any further questions, feel free to reach out and we'll be glad to assist.

Regards,

Microsoft Fabric Community Support Team.