Please how do I refresh a my webpage at a button click?

protected void BtnAddTraining_Click(object sender, EventArgs e)
    {
   bool exist = false;
    string sqcommand = "SELECT count(*) FROM fl_poltype WHERE poltype=@poltype";
    using (SqlCommand cmd = new SqlCommand(sqcommand, cn))
    {
        cn.Open();
        cmd.Parameters.AddWithValue("poltype", TxtPolicyCode.Text);
        exist = (int)cmd.ExecuteScalar() > 0;
    }
    //clear the filed if exist else, insert record
    if (exist)
    {
        LblError.Text = "user already exist";
        TxtPolicyCode.Focus();
        TxtPolicyCode.Text = string.Empty;
        return;

    }
    else
    {
        try
        {

            string insertCommand = "INSERT Into fl_poltype(poltype,poldesc,maxloan,income_account,liability_account,expense_account,vat_account) values(@poltype,@poldesc,@maxloan,@income_account,@liability_account,@expense_account,@vat_account)";
            SqlCommand cmd = new SqlCommand(insertCommand, cn);

            cmd.Parameters.AddWithValue("@poltype", TxtPolicyCode.Text);
            cmd.Parameters.AddWithValue("@poldesc", TxtPolicyName.Text);
            cmd.Parameters.AddWithValue("@maxloan", TxtMaxLoan.Text);
            cmd.Parameters.AddWithValue("@income_account", ddlIncomeCode.SelectedValue);
            cmd.Parameters.AddWithValue("@liability_account", ddlIncomeCode.SelectedValue);
            cmd.Parameters.AddWithValue("@expense_account", ddlLiabilityCode.SelectedValue);
            cmd.Parameters.AddWithValue("@vat_account", ddlVatCode.SelectedValue);



            cmd.ExecuteNonQuery();
            LblError.Text = "SUCCESSFULLY ADDED";
            cleared();
            
            cn.Close();
        }
        catch (Exception ex)
        {
            string log = ex.Message;
        }
        finally
        {
            cn.Close();
        }
    }     

    }