Controller Update method is not working in laravel - laravel-5

Question

I am using laravel 5.2. Controller method store, show, and edit is working fine but update method is not working.
edit.blade is as:
#extends ('layouts.backend')
#section ('content')
<div class="pull-right">
<a class="btn btn-primary" href="{{ route('backend.index') }}"> Back</a>
</div>
<form method="PATCH" action="{{ route('backend.update', $reports->id) }}">
<div>
create report
</div>
<div>
<table>
<tr>
<td>
<div class="form-group required">
<label for="category_id" class="control-label">ID</label>
<input class="form-control" name="id" id="id" type="text" value="{{ $reports->id}}">
</div>
<div class="form-group required">
<label for="category_id" class="control-label">Category</label>
<select class="form-control" id="category" name="category"><option value="" selected="selected">Select</option><option value="1">Agriculture</option><option value="2">Food</option><option value="3">Beverage</option></select>
</div>
<div class="form-group required">
<label for="name" class="control-label">Name</label>
<input class="form-control" name="name" id="name" type="text" value="{{ $reports->name}}">
</div>
<div class="form-group required">
<label for="url" class="control-label">Url</label>
<input class="form-control" name="slug" id="slug" type="text" value="{{ $reports->slug}}">
</div>
<div class="form-group required">
<label>Brief Description</label></br>
<textarea id="brief_des" name="brief_des" rows="12" cols="70" style="width: 80%" >
{{ $reports->brief_des}}
</textarea>
</div>
<div class="form-group required">
<label>Full Description</label></br>
<textarea id="full_des" name="full_des" rows="12" cols="70" style="width: 80%">
{{ $reports->full_des}}
</textarea>
</div>
<input type="submit" value="Update"/>
</td>
<td>
</td>
</tr>
</table>
</div>
{{ Form::token() }}
</form>
#endsection
and Controller update method code is as:
public function update(Request $request, $id){
report::find($id)->update($request->all());
return redirect()->route('backend.index')
->with('success','Product Updated Successfully');
}
and route.php is as:
Route::resource('backend', 'ReportController');
when I am submitting the form then I am getting any update in my database and redirect is not working also.