VS 2010 Error trying to add record to Access 2003 Database with DataAdapter

Public Class frmMain
    Public MoveLeft As Boolean
    Public Conn As New OleDb.OleDbConnection
    Public dbProvider As String
    Public dbSource As String
    Public ds As New DataSet
    Public daCategory As OleDb.OleDbDataAdapter
    Public daLevel As OleDb.OleDbDataAdapter
    Public SQL As String
    Public Action As Integer
        'populate "list by" combobox
        cboListBy.Items.Clear()
        cboListBy.Items.Add("Alphabetically")
        cboListBy.Items.Add("Word category")
        'set form icon
        Me.Icon = My.Resources.UKFlag
        'set panel to be off the right side of the form and therefore not visible. It can be scrolled in from there
        pnlManagement.Left = 1047
 
        'set database stuff
        dbProvider = "PROVIDER=Microsoft.Jet.OLEDB.4.0"
        dbSource = "Data Source=" & Application.StartupPath & "\Vocab.mdb"
        Conn.ConnectionString = dbProvider & ";" & dbSource
        Conn.Open()
        SQL = "SELECT * FROM tblCategory ORDER BY ctName"
        daCategory = New OleDb.OleDbDataAdapter(SQL, Conn)
        daCategory.Fill(ds, "tblCategory")
        Dim bndCategory As New BindingSource
        bndCategory.DataSource = ds.Tables("tblCategory")
        cboCategoryMaint.DataSource = bndCategory
        cboCategoryMaint.ValueMember = "ctID"
        cboCategoryMaint.DisplayMember = "ctName"
 
        SQL = "SELECT * FROM tblLevel"
        daLevel = New OleDb.OleDbDataAdapter(SQL, Conn)
        daLevel.Fill(ds, "tblLevel")
 
        Dim bndLevel As New BindingSource
        bndLevel.DataSource = ds.Tables("tblLevel")
        cboLevelMaint.DataSource = bndLevel
        cboLevelMaint.ValueMember = "lvID"
        cboLevelMaint.DisplayMember = "lvName"
        Conn.Close()
        Conn.Dispose()
        cboLevelMaint.SelectedIndex = -1
        cboCategoryMaint.SelectedIndex = -1
    End Sub

Private Sub btnLevelAdd_Click(sender As System.Object, e As System.EventArgs) Handles btnLevelAdd.Click
        Dim SQL As String = "SELECT * FROM tblLevel"
        Dim insertSql As String = "INSERT INTO tblLevel (lvName) VALUE(@nm)"
        Dim da As New OleDb.OleDbDataAdapter
        da.SelectCommand = New OleDb.OleDbCommand(SQL, Conn)
        Dim ds As New DataSet
        da.Fill(ds, "tblLevel")
        Dim dt As DataTable = ds.Tables("tblLevel")
        Dim newRow As DataRow = dt.NewRow()
        newRow("lvName") = cboLevelMaint.Text
        dt.Rows.Add(newRow)
        Dim insertCmd As New OleDb.OleDbCommand(insertSql, Conn)
        insertCmd.Parameters.Add("@nm", CType(SqlDbType.NVarChar, OleDb.OleDbType), 10, "lvName")
        da.InsertCommand = insertCmd
        da.Update(ds, "tblName")
        ShowAdded()
    End Sub