Can someone help me take a look is my code have missing i am no success clear my datagridview data

Below is my code

 Private dtable As DataTable = New DataTable()
    Private lstName As List(Of String) = New List(Of String)()
    Private control As Boolean = True

Private Sub DataGridView1_CellClick(ByVal sender As Object, ByVal e As DataGridViewCellEventArgs) Handles DataGridView1.CellClick
        Dim name As String = DataGridView1.Columns(DataGridView1.CurrentCell.ColumnIndex).HeaderText

        If Not lstName.Contains(name) Then
            lstName.Add(name)
            dtable.Columns.Add(name)

            If control Then
                For x As Integer = 0 To DataGridView1.Rows.Count - 1 - 1
                    Dim s As String = DataGridView1.Rows(x).Cells(DataGridView1.CurrentCell.ColumnIndex).Value.ToString()
                    dtable.Rows.Add(s)
                Next
                control = False
            Else
                For y As Integer = 0 To dtable.Rows.Count - 1
                    dtable.Rows(y)(name) = DataGridView1.Rows(y).Cells(DataGridView1.CurrentCell.ColumnIndex).Value.ToString()
                Next
            End If
        End If

        DataGridView2.DataSource = dtable
    End Sub

        dtable.Clear()
        lstName.Clear()

program current status

after clear database datagridview 2 still no clear complete