cannot change userform combobox range error 457

hi
a userform has this code

Option Explicit
Private Sub ComboBox1_Change()
    Dim idx As Long
    Dim rsource As Long
    Dim rowsource As Long
    Dim i As Long
    Dim rw As Long
    Dim arrIDS As Variant
    Dim arrFilteredIDS As Variant
    idx = ComboBox1.ListIndex
    If idx <> -1 Then
        ListBox1.Clear
        With Sheets("repairs")
            With .Range("a2", .Range("a" & Rows.Count).End(xlUp))'changed to("f2", .Range("f"   ect
                arrIDS = Evaluate("TRANSPOSE(repairs!" & .Address & "&""-""&ROW(" & .Address & "))")
            End With
        End With
        arrFilteredIDS = Filter(arrIDS, ComboBox1.Value, True)
        For i = LBound(arrFilteredIDS) To UBound(arrFilteredIDS)
            rw = Replace(arrFilteredIDS(i), ComboBox1.Value & "-", "")
            With ListBox1
                .AddItem ComboBox1.Value
              '  .List(.ListCount - 1, 1) = Sheets("repairs").Range("a" & rw).Value
                .List(.ListCount - 1, 2) = Sheets("repairs").Range("b" & rw).Value
                .List(.ListCount - 1, 3) = Sheets("repairs").Range("c" & rw).Value
                .List(.ListCount - 1, 4) = Sheets("repairs").Range("i" & rw).Value
                .List(.ListCount - 1, 5) = Sheets("repairs").Range("j" & rw).Value
                .List(.ListCount - 1, 6) = Sheets("repairs").Range("f" & rw).Value
                .List(.ListCount - 1, 7) = Sheets("repairs").Range("l" & rw).Value
                .List(.ListCount - 1, 8) = Sheets("repairs").Range("n" & rw).Value
                
                Dim Rownum As Long
                .ColumnWidths = "1.0 in;0;3.0in;1.0 in;1.5 in;1.5 in;1.5 in"
            End With
        Next i
    End If
End Sub
Private Sub TextBox1_Change()
'Me.TextBox1.Value = ListBox6.ListCount
End Sub
Private Sub TextBox2_Change()
End Sub

Private Sub CommandButton1_Click()
Unload Me
End Sub

Private Sub CommandButton2_Click()
Unload Me
End Sub

Private Sub ListBox1_Click()

End Sub

Private Sub UserForm_Initialize()

 Call RemoveCaption(Me)

    With Application
        Width = .Width
        Height = .Height
    End With






    Dim dicIDs As Object
    Dim rngIDs As Range
    Dim cl As Range
   
    With Sheets("repairs")
        Set rngIDs = .Range("a2", .Range("a" & Rows.Count).End(xlUp))  'changed to ("f2", .Range("f"   ect
    End With
    Set dicIDs = CreateObject("Scripting.Dictionary")
    For Each cl In rngIDs.Cells
        If Not dicIDs.exists(cl.Text) Then
            dicIDs.Add cl.Value, cl.Text
        End If
    Next cl
    ComboBox1.List = dicIDs.keys
End Sub

this works fine if range is a2 but if I change it to f2 it has error457 (this key is already associated with an element of this collection)can anyone tell me why
it will not work please
cheers colin