Prevent PhpSpreadSheet from adding the # symbol - php

Question

I am working with PhpSpreadsheet. When I use a formula that copies cell values, it adds to the formula the # symbol. This cause constant an error.
I need to prevent PhpSpreadsheet from adding this # symbol.
When I remove the #, the formula works perfectly.
//** Create a new Spreadsheet Object **//
$spreadsheet = new \PhpOffice\PhpSpreadsheet\Spreadsheet();
$worksheet = $spreadsheet->getActiveSheet(); //get current active sheet (first sheet)
//** Set and load the reader **//
$inputFileName = $basePath;
$reader = new \PhpOffice\PhpSpreadsheet\Reader\Xlsx(); // Create a new Reader of type xlsx
$reader->setReadDataOnly(false); // Keeping the style
$spreadsheet = $reader->load($inputFileName); // Load $inputFileName to a Spreadsheet Object
$spreadsheet->getActiveSheet()->fromArray($ufields, null, 'A8', true);
$attrs = $spreadsheet->getActiveSheet()->getCell("A10")->getFormulaAttributes();
$attrs['t'] = 'array';
$spreadsheet->getActiveSheet()->getCell("A10")->setFormulaAttributes($attrs);
$spreadsheet->getActiveSheet()->setCellValue("A10",'=IF(all_details!A8:I8<>"", all_details!A8:I8, "")');
$writer = new \PhpOffice\PhpSpreadsheet\Writer\Xlsx($spreadsheet);
$writer->setPreCalculateFormulas(false);
$writer->save($inputFileName);
//Export sheet code
header('Content-Type: application/vnd.ms-excel');
header('Content-Disposition: attachment;filename="'.$reportOriginalname.'"');
header('Cache-Control: max-age=0');
** I read and tried the solution suggested here, but it didn't work for me.