Syntax error in UPDATE statement.

Private Sub update_prosedure()
        connection = New OleDbConnection(connetionString)
        Dim cmd As New OleDb.OleDbCommand

        cmd.Connection = connection

        Dim a As String = "UPDATE material Set ([NOREG]=@NOREG], [DATE]=[@DATE], [SUPPLIER]=[@SUPPLIER], [NOSJL]=[@NOSJL], [PO]=[@PO], [STYLE]=[@STYLE], [DESCRIPTION]=[@descrip], [COLOR]=[@COLOR], [SIZE]=[@SIZE], [QTY]=[@QTY], [UOM]=[@UOM], [NOCSTMBN]=[@NOCSTMBN]) WHERE [NOREG]=[@NOREG]"
        With cmd.Parameters
            .AddWithValue("@NOREG", txt_noreg.Text)
            .AddWithValue("@DATE", txt_date.Text)
            .AddWithValue("@SUPPLIER", txt_supplier.Text)
            .AddWithValue("@NOSJL", txt_nosjl.Text)
            .AddWithValue("@PO", txt_po.Text)
            .AddWithValue("@STYLE", txt_style.Text)
            .AddWithValue("@descrip", txt_descrip.Text)
            .AddWithValue("@COLOR", txt_color.Text)
            .AddWithValue("@SIZE", txt_size.Text)
            .AddWithValue("@QTY", txt_qty.Text)
            .AddWithValue("@UOM", cmb_uom.Text)
            .AddWithValue("@NOCSTMBN", txt_nocstmbn.Text)
        End With
        connection.Open()
        cmd.CommandText = a
        '  cmd = New OleDbCommand(a, connection)
        cmd.ExecuteNonQuery()

        ref_table()
        connection.Close()
        clear()

    End Sub