Option Explicit
Sub DelRng()

    Dim Rng As Range
    Dim DelRng As Range
    Dim c As Range

    On Error Resume Next
    Set Rng = Application.InputBox("Выделите диапазон для очистки повторяющихся значений", "Задание диапазона", Type:=8)
    On Error GoTo 0
    
    If Rng Is Nothing Then Exit Sub
    
    For Each c In Rng
        If WorksheetFunction.CountIf(Rng, c) > 1 Then
            If DelRng Is Nothing Then Set DelRng = c Else Set DelRng = Union(DelRng, c)
        End If
    Next
    
    DelRng.Clear
    
End Sub