DataAdapter Update Problems

Hi, I am populating a datagrid with data from one sql table, I add additional columns and then wish to write it back out to another table. I have written the following code to acheive this, however it keeps throwing the follwing exception - "Update requites a valid UpdateComman when passed a DataRow collection with modified rows"

I've looked and I can see what the problem is, can anybody help please?

 Private Sub FillData()
'SQL connection
Me.sqlconnection = New System.Data.SqlClient.SqlConnection
Me.sqlconnection.ConnectionString = ConfigurationSettings.AppSettings("CuroConnection")

Dim sql As String
If Request("action") = "gen" Then
sql = "select item from tblPickList where GroupName = 'xxx'AND Category = '" & Category2 & "' ORDER BY item ASC"
ElseIf Request("action") = "fav" Then
sql = "select identifiertext as item from tblfavourites where HRID = " & Session("hrid") & " and type = 3 ORDER BY identifiertext ASC"
ElseIf Request("action") = "spec" Then
sql = "select item from tblPickList where GroupName = '" & GroupID & "' AND Category = '" & Category2 & "' ORDER BY item ASC"
End If

ds = New DataSet
da = New SqlClient.SqlDataAdapter(sql, sqlconnection)

Try
sqlconnection.Open()
da.Fill(ds, "tblPickListTemp")
sqlconnection.Close()
Catch ex As Exception
sqlconnection.Close()
End Try

ds.Tables(0).Columns.Add("HRID")
ds.Tables(0).Columns.Add("Flag")
'may possibly add a favourites column here at a later date to ensure no duplication

Dim dr As DataRow
For Each dr In ds.Tables("tblPickListTemp").Rows
dr("HRID") = Session("hrid")
dr("Flag") = 0
Next

DgrdFavourites.DataSource = ds
DgrdFavourites.DataBind()
End Sub

Public Sub CreateTempRecords()

'SQL connection
Me.sqlconnection = New System.Data.SqlClient.SqlConnection
Me.sqlcommand = New System.Data.SqlClient.SqlCommand
Me.da = New SqlClient.SqlDataAdapter
Me.sqlconnection.ConnectionString = ConfigurationSettings.AppSettings("CuroConnection")

Dim sql As String
sql = "Insert into tblPickListTemp (Item, HRID, Flag) values (@Item, @HRID, @Flag)"
sqlcommand.CommandText = sql
sqlcommand.Connection = sqlconnection

sqlcommand.Parameters.Add("@Item", "Item")
sqlcommand.Parameters.Add("@HRID", "HRID")
sqlcommand.Parameters.Add("@Flag", "Flag")
da.InsertCommand = sqlcommand
da.Update(ds.Tables(0))
End Sub