Problem on Dompdf, Invalid characters passed for attempted conversion, these have been ignored

Problem on Laravel Dompdf: Invalid characters passed for attempted conversion, these have been ignored

My Controller public function CasePDF($id) { // echo $id; $case_view = Case_a::findOrFail($id); $details = Case_details::where('case_id' , $id)->value('case_details'); // echo "string"; // return view('pdf.casepdf', compact('case_view','details')); if ($case_view->added_by != Auth::user()->id) { abort(404); } $caseNumber = $case_view->case_number; $caseNumber .= ".pdf";

  $pdf = PDF::loadView('pdf.casepdf', compact('case_view','details'));

  return $pdf->download($caseNumber);
}

via Chebli Mohamed