DataGridView shows duplicate (Double) values

public void showEvents()
        {
            cmd2 = new MySqlCommand();
            String cmdString2 = "SELECT d.DId, d.Date,d.Time,d.Temp, d.DLane, d.DVentilation, d.DRemarks FROM date d, container c, Plugoff p where c.GKId=d.GKId  AND c.ContainerNo like ('" + txtContNo.Text + "%') AND c.GKId = ('" + txtUsed.Text + "') ";
            adp = new MySqlDataAdapter(cmdString2, con);
            ds = new DataSet();
            adp.Fill(ds, "cont");
            dataGridView1.DataSource = ds.Tables["cont"];
        }