How to save many selected in check box list

This is my code behind

Private Sub BindCheckBoxListIssue()

        Dim dt As New DataTable()
        Dim dbconn As New SqlConnection(strCon)
        Try
            dbconn.Open()
            Dim strSql As String = "SELECT * FROM MonitorIssue"
            Dim dbcomm As New SqlCommand(strSql, dbconn)
            Dim SqlDa As New SqlDataAdapter(dbcomm)

            SqlDa.Fill(dt)
            If (dt.Rows.Count > 0) Then
                chklstIsu.DataSource = dt
                chklstIsu.DataTextField = "Issue"
                chklstIsu.DataValueField = "Issue"
                chklstIsu.DataBind()
            End If

            For i As Integer = 0 To 15
                dt.Rows(i)("IsSelected").ToString()
                chklstIsu.Items(i).Selected = Convert.ToBoolean(dt.Rows(i)("IsSelected"))
            Next

            dbconn.Close()

            setMsg(Me, "Record saved", "strKey")
        Catch
            setMsg(Me, "Record save failed", "strKey")
        End Try
    End Sub

    Private Sub UpdateIssue()
        Dim conn As New SqlConnection()
        Dim cmd As New SqlCommand
        Dim strSql = ""

        Try
            cmd.Connection = conn
            conn.Open()

            strSql = "UPDATE MonitorIssue SET IsSelected = @IsSelected WHERE Issue = @Isu"
            For Each item As ListItem In chklstIsu.Items
                cmd.Parameters.Clear()
                cmd.Parameters.AddWithValue("@IsSelected", item.Selected)
                cmd.Parameters.AddWithValue("@ListingId", item.Value)
                cmd.ExecuteNonQuery()
            Next

            conn.Close()

            setMsg(Me, "Record saved", "strKey")
        Catch
            setMsg(Me, "Record save failed", "strKey")
        End Try
    End Sub