Osveževanje podatkov v comboboxu

Zanima me, kako bi dodal/osežil seznam podatkov v combobox po tem ko sem že naložil podatke v dataset, iz katerega se podatke črpa za prikaz in v bazo dodal še nekaj novih podatkov. Ni mi jasno zakaj se ne naložijo ob vsakem odiranju forma ponovno podatki iz baze v dataset in me zanima kaj bi moral v kodi spremeniti da bi se stvar osveževala oz posodabljala ob vsakem odpiranju? v Formu imam tudi en gumb ki bi mi stvari ponovno naložil vendar mi ob pristisku na gumb javi napake:
************** Exception Text **************
System.ArgumentException: This causes two bindings in the collection to bind to the same property.
Parameter name: binding
at System.Windows.Forms.ControlBindingsCollection.CheckDuplicates(Binding binding)
at System.Windows.Forms.Binding.CheckBinding()
at System.Windows.Forms.Binding.SetBindableComponent(IBindableComponent value)
at System.Windows.Forms.ControlBindingsCollection.AddCore(Binding dataBinding)
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Program:
public partial class Projekt : Form
{

string DN, Ime, Opis;
int ID;
//static int i = 0; //index for strArraylist
DateTime Datum;

public Projekt()
{
InitializeComponent();
napolniProjekt();
napolniDelavca();

}

private void Projekt_Load(object sender, EventArgs e)
{
// TODO: This line of code loads data into the 'bazaDataSet1.Storitve' table. You can move, or remove it, as needed.
this.storitveTableAdapter.Fill(this.bazaDataSet1.Storitve);

}
public void napolniProjekt()
{
DataViewManager dview = new DataViewManager();

OleDbConnection myConn = null;
OleDbDataAdapter Adapter=null;
DataSet dset=null;
DataBindings.Clear();
try
{
//open the connection to the database
myConn = new OleDbConnection();
myConn.ConnectionString = connection();
myConn.Open();
}
catch (OleDbException ex)
{
MessageBox.Show("Error in connection ..." + ex.Message);
}

string sqlStr = "SELECT ID_Projekta,Delovni_nalog,Ime,Opis,Dat_Zacetka FROM Projekt WHERE Zaprt=false";

//Instantiate a DataAdapter by passing the sqlStr and Connection.
//now data is in raw form
Adapter = new OleDbDataAdapter(sqlStr, myConn);

//Instantiate a DataSet
dset = new DataSet();
dset.Clear();
//Gets a collection that provides the master mapping
// between a source table and a DataTable
Adapter.TableMappings.Add("Table", "Projekt");

Adapter.Fill(dset);
dview = dset.DefaultViewManager;

comboBox1.DataSource = dview;
comboBox3.DataSource = dview;
this.comboBox1.DisplayMember = "Projekt.Ime";
this.comboBox3.DisplayMember = "Projekt.Delovni_nalog";

//DataBinding for the TextBox controls

this.datum.DataBindings.Add("Text", dview, "Projekt.Dat_Zacetka");

this.textBox3.DataBindings.Add("Text", dview, "Projekt.Opis");
this.textBox4.DataBindings.Add("Text", dview, "Projekt.ID_Projekta");

// Close the connection to the database.

myConn.Close();

}
private void button3_Click(object sender, EventArgs e)
{
DataBindings.Clear();
napolniProjekt();
}
Prosim za pomoč, če kdo ve, kaj je treba spremenit ali padodatk da stvar dela tako kot želim.

Hvala