Makro DEBUG hatası

Private Sub OptionButton1_Click()
If Me.ComboBox1.Text = "" Then Exit Sub
Dim b()
For a = 3 To Range("AA" & Rows.Count).End(xlUp).Row
    If Me.ComboBox1.Text = Cells(a, "AA") Then
        If Cells(a, "X") = 2 Or Cells(a, "X") = 3 Then
            say = say + 1
            ReDim Preserve b(1 To 3, 1 To say)
            b(1, say) = Cells(a, "B")
            b(2, say) = Cells(a, "C")
            b(3, say) = Cells(a, "D")
        End If
    End If
Next

With Me.ListBox1
.RowSource = vbNullString
.Clear
If IsEmpty(say) Then Exit Sub
.ColumnCount = UBound(b())
.Column = b
.ColumnWidths = "420,190,95"
End With
End Sub