Textbox format "dd/mm/yyyy"

Hej
klikker MonthView1(01-01-2018)
Textbox1= 01-01-2018
Range("A2").Value =01-01-2018
klikker ind i Textbox1 tilføjer 9(måned 19) 01-019-2018
Excel ændre til 19-01-2018?????

Private Sub MonthView1_DateClick(ByVal DateClicked As Date)
    On Error Resume Next
    TextBox1 = Format(DateClicked, "dd/mm/yyyy")
End Sub

Private Sub TextBox1_Change()
    On Error GoTo ErrorHandler
    Application.EnableEvents = False 'disable Worksheet_SelectionChange, Worksheet_Change
    If Me.TextBox1.Text = "" Then
    'do nothing
    ElseIf Me.TextBox1.Text <> "" Then
    Me.TextBox1.Value = Format(TextBox1.Value, "dd/mm/yyyy")
    If IsDate(Me.TextBox1.Value) = True Then
    Me.TextBox1.ForeColor = RGB(0, 0, 0)
    Range("A2").Value = CDate(Me.TextBox1.Value)
    Else
    Me.TextBox1.ForeColor = RGB(250, 0, 0)
    Range("A2").ClearContents
    End If
    End If
ErrorHandler:
    Application.EnableEvents = True 'disable Worksheet_SelectionChange, Worksheet_Change
End Sub