错误 谁能帮忙看下？？？

        private void btnPrint_Click(object sender, EventArgs e)
        {

            using (OleDbConnection con = new OleDbConnection(AccHelper.ConnectionString))
            {
                    string sqlInsert = "insert into kehu(kehu_Money,kehu_Upmoney) values ("+ Convert.ToDouble(this.lbMoney.Text) +",'" +    this.lbUpper.Text +"') where kehu_fax_No = '"+ this.txtInvoice.Text +"'";
                 con.Open();
                OleDbCommand com = new OleDbCommand(sqlInsert,con);

                int count = com.ExecuteNonQuery();
                if (count > 0)
                {
                PrintInvoice pro = new PrintInvoice(this.txtInvoice.Text);
                pro.Show();
            }
            }
        }

里面这个Access语句有错误 提示缺少sql结束符“；”，谁能看一下是什么错误吗？