ASP.Net Core Error: The process cannot access the file because it is being used by another process

Hello Sir,

Please suggest i want to download excel file in asp.net core

but giving error

IOException: The process cannot access the file 'E:\Backup Project\TESTEYNEW1\WebApplication1\WebApplication1\wwwroot\Data\FinalReport1.xlsx' because it is being used by another process.

this is when i click buttin inside index Exporrt data method called when this method called report generated insde a data folder then after download action button click first time it will work when again if i click generate report or download report then this mesage come.

        [HttpPost]
        public IActionResult Index(OutWardReport outWard)
        {
            DataTable dt = new DataTable();
            DataSet Ds = new DataSet();
            string query = "";
            int id = 0;
            dt = obj.GetReport(id);
           if (dt.Rows.Count > 0)
            {
               Ds.Tables.Add(dt);
               ExportDataSet(Ds, "FinalReport.xlsx");
               ViewBag.Message = String.Format("Hurrah!!!!!! report generated");
            }
            return View();
        }

        public void ExportDataSet(DataSet ds, string destination)
        {
            using (var workbook = SpreadsheetDocument.Create(destination, DocumentFormat.OpenXml.SpreadsheetDocumentType.Workbook))
            {
                var workbookPart = workbook.AddWorkbookPart();

                workbook.WorkbookPart.Workbook = new DocumentFormat.OpenXml.Spreadsheet.Workbook();

                workbook.WorkbookPart.Workbook.Sheets = new DocumentFormat.OpenXml.Spreadsheet.Sheets();

                foreach (System.Data.DataTable table in ds.Tables)
                {
                    var sheetPart = workbook.WorkbookPart.AddNewPart<WorksheetPart>();
                    var sheetData = new DocumentFormat.OpenXml.Spreadsheet.SheetData();
                    sheetPart.Worksheet = new DocumentFormat.OpenXml.Spreadsheet.Worksheet(sheetData);
                    DocumentFormat.OpenXml.Spreadsheet.Sheets sheets = workbook.WorkbookPart.Workbook.GetFirstChild<DocumentFormat.OpenXml.Spreadsheet.Sheets>();
                    string relationshipId = workbook.WorkbookPart.GetIdOfPart(sheetPart);
                    uint sheetId = 1;
                    if (sheets.Elements<DocumentFormat.OpenXml.Spreadsheet.Sheet>().Count() > 0)
                    {
                        sheetId =
                            sheets.Elements<DocumentFormat.OpenXml.Spreadsheet.Sheet>().Select(s => s.SheetId.Value).Max() + 1;
                    }
                    DocumentFormat.OpenXml.Spreadsheet.Sheet sheet = new DocumentFormat.OpenXml.Spreadsheet.Sheet() { Id = relationshipId, SheetId = sheetId, Name = table.TableName };
                    sheets.Append(sheet);
                    DocumentFormat.OpenXml.Spreadsheet.Row headerRow = new DocumentFormat.OpenXml.Spreadsheet.Row();
                    List<String> columns = new List<string>();
                    foreach (System.Data.DataColumn column in table.Columns)
                    {
                        columns.Add(column.ColumnName);
                        DocumentFormat.OpenXml.Spreadsheet.Cell cell = new DocumentFormat.OpenXml.Spreadsheet.Cell();
                        cell.DataType = DocumentFormat.OpenXml.Spreadsheet.CellValues.String;
                        cell.CellValue = new DocumentFormat.OpenXml.Spreadsheet.CellValue(column.ColumnName);
                        headerRow.AppendChild(cell);
                    }
                    sheetData.AppendChild(headerRow);
                    foreach (System.Data.DataRow dsrow in table.Rows)
                    {
                        DocumentFormat.OpenXml.Spreadsheet.Row newRow = new DocumentFormat.OpenXml.Spreadsheet.Row();
                        foreach (String col in columns)
                        {
                            DocumentFormat.OpenXml.Spreadsheet.Cell cell = new DocumentFormat.OpenXml.Spreadsheet.Cell();
                            cell.DataType = DocumentFormat.OpenXml.Spreadsheet.CellValues.String;
                            cell.CellValue = new DocumentFormat.OpenXml.Spreadsheet.CellValue(dsrow[col].ToString()); //
                            newRow.AppendChild(cell);
                        }
                        sheetData.AppendChild(newRow);
                    }                   
                }
                
                var path = Path.Combine(
                    Directory.GetCurrentDirectory(), "wwwroot","Data", "FinalReport1.xlsx");  
                
                FileInfo file = new FileInfo(path);
                //file.OpenRead();
                if (file.Exists)//check file exsit or not
                {
                    file.Delete();
                    workbook.SaveAs(path);
                }
                else
                {
                    workbook.SaveAs(path);
                }
                workbook.Close();
                GC.WaitForFullGCComplete();
                GC.WaitForPendingFinalizers();
                GC.Collect();
                //ExcelEngineObject.Dispose();                              
            }
        }
        public async Task<IActionResult> Download()
        {            
            var path = Path.Combine(
                 Directory.GetCurrentDirectory(), "wwwroot", "Data", "FinalReport1.xlsx");
            var memory = new MemoryStream();
            //memory.Close();
            using (var stream = new FileStream(path, FileMode.Open,FileAccess.ReadWrite,FileShare.ReadWrite))
            {
              await stream.CopyToAsync(memory);
                stream.Close();
            }
            memory.Position = 0;
            return File(memory, GetContentType(path), Path.GetFileName(path));
        }
        private string GetContentType(string path)
        {
            var types = GetMimeTypes();
            var ext = Path.GetExtension(path).ToLowerInvariant();
            return types[ext];
        }
        private Dictionary<string, string> GetMimeTypes()
        {
            return new Dictionary<string, string>
            {
                {".txt", "text/plain"},
                {".pdf", "application/pdf"},
                {".doc", "application/vnd.ms-word"},
                {".docx", "application/vnd.ms-word"},
                {".xls", "application/vnd.ms-excel"},
                {".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"},
                {".png", "image/png"},
                {".jpg", "image/jpeg"},
                {".jpeg", "image/jpeg"},
                {".gif", "image/gif"},
                {".csv", "text/csv"}
            };
        }