[Solved] ASP.Net Error: The modifier public is not valid for this item

I have this code that helps to clear the textbox after submitting data, but is generating error, i wanted to clear all textbox after submit

error

Error	CS0106	The modifier 'public' is not valid for this item

        protected void btnsave_Click(object sender, EventArgs e)
        {
            int inserted = 0;

            if (txtqty.Text.Length > 0 && ddprice.Text.Length > 0)
            {
                float qty2 = !string.IsNullOrEmpty(txtqty.Text.Trim()) ? float.Parse(txtqty.Text.Trim()) : float.Parse("0"); ;
                float price = !string.IsNullOrEmpty(ddprice.SelectedItem.Text.Trim()) ? float.Parse(ddprice.SelectedItem.Text.Trim()) : float.Parse("0"); ;

                float totalprice = qty2 * price;
                float finalprice = totalprice;

                if (txtqty.Text.Length > 0 && ddprice.Text.Length > 0)
                {
                    float disc = !string.IsNullOrEmpty(ddiscount.SelectedItem.Text.Trim()) ? float.Parse(ddiscount.SelectedItem.Text.Trim()) : float.Parse("0"); ;
                    
                    float sum = totalprice - disc;
                    float gtotal = sum;

                    using (SqlConnection con = new SqlConnection())
                    {
                        con.ConnectionString = str;
                        using (SqlCommand cmd = new SqlCommand())
                        {
                            cmd.CommandType = CommandType.Text;
                            cmd.Connection = con;
                            //Change the query like below
                            //Make sure the column name matches the with the name provided in code as per your table
                            cmd.CommandText = "INSERT INTO DAILYSales (AttendedBy,Staff_Assigned,Customer_Phone,Job_Category,Quantity,Price,Material,Width,Height,Unit,Discount,After_Discount,Sum) VALUES(@AttendedBy,@Staff_Assigned,@Customer_Phone,@Job_Category,@Quantity,@Price,@Material,@Width,@Height,@Unit,@Discount,@After_Discount,@Sum)";
                            cmd.Parameters.AddWithValue("@AttendedBy", HttpContext.Current.User.Identity.Name);
                            cmd.Parameters.AddWithValue("@Job_Category", ddlproductcategory.SelectedItem.Text);
                            cmd.Parameters.AddWithValue("@Staff_Assigned", ddlstaff.SelectedItem.Text);
                            cmd.Parameters.AddWithValue("@Customer_Phone", ddlphone.SelectedItem.Text);
                            cmd.Parameters.AddWithValue("@Quantity", txtqty.Text);
                            cmd.Parameters.AddWithValue("@Price", ddprice.SelectedItem.Text);
                            cmd.Parameters.AddWithValue("@Material", ddlmaterial.SelectedItem.Text);

                            
                            cmd.Parameters.AddWithValue("@Width", txtwidth.Text);
                            cmd.Parameters.AddWithValue("@Height", txtheight.Text);
                            cmd.Parameters.AddWithValue("@Discount", ddiscount.SelectedItem.Text);
                            cmd.Parameters.AddWithValue("@Unit", txtunit.Text);

                            cmd.Parameters.AddWithValue("@Sum", totalprice);
                            cmd.Parameters.AddWithValue("@After_Discount", sum);
                            con.Open();
                            inserted = cmd.ExecuteNonQuery();
                            con.Close();
                            BindGridreport();
                            string message = string.Empty;
                            {
                                // lblMessage2.Visible = true;
                                /// lblMessage2.Text = "Data Submitted Successfully";
                            }
                            ScriptManager.RegisterClientScriptBlock(btnsave, this.GetType(), "alert", "<script>alert('Data Submitted Successfully ... !!')</script>", false);
                            // lblMessage2.Text = "Inserted Quantity Is Higher than  stock " + GetQuantity().ToString();
                        }
                    }

                }

                CleartextBoxes(this);
            }
            public void CleartextBoxes(Control parent)
            {
                foreach (Control c in parent.Controls)
                {
                    if ((c.GetType() == typeof(TextBox)))
                    {

                        ((TextBox)(c)).Text = "";
                    }

                    if (c.HasControls())
                    {
                        CleartextBoxes(c);
                    }
                }
            }
            // this.BindGrid();
        }