i am working on c# windows form application and have the error No value given for one or more required parameters. because i want to get element by string code

private void button2_Click(object sender, EventArgs e)
{  
 String connectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data" + @" Source = company.accdb";               
                String query = "select * from [Table] where [code] ="+txt_code.Text;
                
                DataSet ds = new DataSet();

                OleDbConnection conn = new OleDbConnection(connectionString);
 

                    conn.Open();
                    OleDbDataAdapter da = new OleDbDataAdapter(query, conn);
                    da.Fill(ds,"Table");
                    conn.Close();
                    txt_price.Text = ds.Tables["Table"].Rows[0]["price"].ToString();
                    txt_number.Text = ds.Tables["Table"].Rows[0]["number"].ToString();
                    txt_des.Text = ds.Tables["Table"].Rows[0]["description"].ToString();
                    double w = double.Parse(txt_price.Text);
                    double tax = w * 0.16;
                    txt_tax.Text = tax.ToString();
                    w = w - tax;
                    txt_w.Text = w.ToString();
}