c# - OpenXml - Unable to create and assign stylesheet to MS Excel -

i trying create excel spreadsheet using openxml 2.0 , c#. can able create plain excel without format data table values database. but, when try create new style apply on specific fields, excel created unable open , throws error message:

excel has stopped working.

below code use create stylesheet.

spreadsheetdocument spreadsheetdocument = spreadsheetdocument.create(filepath,spreadsheetdocumenttype.workbook);  // add workbookpart document. workbookpart workbookpart = spreadsheetdocument.addworkbookpart(); workbookpart.workbook = new workbook(); workbookpart.workbook.save();  // add worksheetpart workbookpart. worksheetpart worksheetpart = workbookpart.addnewpart<worksheetpart>();    worksheetpart.worksheet = new worksheet(new sheetdata()); worksheetpart.worksheet.save();             workbookstylespart stylepart = spreadsheetdocument.workbookpart.addnewpart<workbookstylespart>();  stylesheet stylesheet = new stylesheet(); cellformats cellformats = new cellformats() { count = (uint32value)1u }; cellformat cellformat = new cellformat(new alignment { wraptext = true }); cellformats.append(cellformat); stylesheet.append(cellformats);  stylesheet.save(stylepart); //stylepart.stylesheet = stylesheet; //stylepart.stylesheet.save();  uint32value styleindex = stylesheet.cellformats.count; 

can please fix issue. if comment stylesheet creation part, excel generated , accessing perfectly. can 1 check , explain going wrong.