VBA VLookup allow the user to select the filename on directory
===

I have been attempting to insert a VLookup formula into a column using VBA. The Table_array is variable and changes each month, so I would like a dialog box to sepcify the file I want to use. The Table_array is in an identical format each month and my formula so far is as follows:

Sub VlookupMacro()
    
    Dim FirstRow As Long
    Dim FinalRow As Long
    Dim myValues As Range
    Dim myResults As Range
    Dim myFile As Range
    Dim myCount As Integer
    
    Set myFile = Application.GetOpenFilename("Excel Files (*.xls), *.xls")
    
        Set myValues = Application.InputBox("Please select the first cell in the column with the values that you're looking for", Type:=8)
    
            Set myResults = Application.InputBox("Please select the first cell where you want your lookup results to start ", Type:=8)
    
                Range(myResults, myResults.Offset(FinalRow - FirstRow)).Formula = _
                "=VLOOKUP(" & Cells(FirstRow, myValues.Column) & ", myFile.value($A$2:$B$U20000), 5, False)"
    
                If MsgBox("Do you want to convert to values?", vbYesNo) = vbNo Then Exit Sub
    
    Columns(myResults.Column).Copy
    Columns(myResults.Column).PasteSpecial xlPasteValues
    Application.CutCopyMode = False 
    
    End Sub

I'm getting an issue with 'myFile' at the moment where the code doesn't proceed past the Set = myFile line. Any suggestions or amendments would be most welcome. Other than that the variable file will never be longer than 20000 lines (which is why I have fixed the range in the formula) and we will always pick up column 5.