VBA Filtered LastRow to specific row where the header is located

[decadence]

Hi, I am having a problem where I am trying to add specific text to a filtered column in the visible cells only but the code below adds the text below the used range. I would like to only add the text to the filtered visible cells not including the header, can some one help with this please

Sub AddText()
    Dim xTitleId As Variant, Rng As range, Rng2 As range, x As range, i As range, c As range, addStr As String
    Application.ScreenUpdating = False
    For Each i In range("A1:Z2")
    Select Case i.value2
    Case "IPN", "Part", "Part Number"
        If Not Rng Is Nothing Then
            Set Rng = Union(Rng, i)
        Else
            Set Rng = i
        End If
            End Select
        Next
    If Rng Is Nothing Then Exit Sub
    Application.ScreenUpdating = False
    If Not Rng Is Nothing Then
        Set Rng = Rng.Resize(Cells(Rows.Count, Rng.Column).End(xlUp).row).Offset(1)
    Rng.AutoFilter Field:=1, Criteria1:="<>*DNF_*", Operator:=xlAnd, Criteria2:="<>*FID_*"
    For Each i In range("A1:Z2")
    Select Case i.value2
    Case "IPN", "Part", "Part Number"
        If Not Rng2 Is Nothing Then
            Set Rng2 = Union(Rng, i)
        Else
            Set Rng2 = i
        End If
            End Select
        Next
    If Rng2 Is Nothing Then Exit Sub
    Application.ScreenUpdating = False
    If Not Rng2 Is Nothing Then
        Set Rng2 = Rng2.Resize(Cells(Rows.Count, Rng.Column).End(xlUp).row).Offset(1)
    On Error Resume Next
    addStr = Application.InputBox("Add Prefix", xTitleId, "", Type:=2)
    If addStr = "False" Then
    ActiveSheet.AutoFilterMode = False
    MsgBox "No Prefixes Added!"
    Exit Sub
    Else
    Application.ScreenUpdating = False
    For Each x In Rng2.SpecialCells (xlCellTypeVisible)
    x.Value = addStr & x.Value
    Next x
    End If
    End If
    End If
    ActiveSheet.AutoFilterMode = False
    On Error GoTo 0
    Application.ScreenUpdating = True
End Sub