1. Make a backup of your workbook.
2. Open your workbook and ALT+F11
3. Locate your Workbook name in Project Explorer Window
4. Right click on your workbook name > Insert > Module
5. Copy & Paste the below code in this module

Now, you can call this function like

=GetPivotRange(E5)

Where E5 is any cell in your Pivot Table

' *** Macro by eforexcel.com *****
Function GetPivotRange(Cell As Range) As String
    GetPivotRange = Application.ConvertFormula(Cell.PivotTable.SourceData, xlR1C1, xlA1)
End Function