500 Internal Server Error

in the console it will print

requisition/15/files:1 Failed to load resource: the server responded with a status of 500 (Internal Server Error

what I am trying to do is uploading a file + change status through a modal form without refreshing and closing the modal

I think I didnot passed my data correctly to the ajax request can anyone solve it for me?

controller

 public function storeFile(Request $request , $id) {

        if ($request->ajax()) {

        $validator = Validator::make($request->all(), [
       // $request->validate([
            'acc_status'            => 'required',
           'acc_document'          => 'required|mimes:doc,docx,pdf,txt,zip|max:2000',
        ]);
       if ($validator->fails())
        {
                        return response()->json(['errors'=>$validator->errors()]);
        }
            $requisition = Requisition::find($id);
            $requisition->acc_status =  $request->get('acc_status');

             if($request->hasFile('acc_document'))
            {

            $requisitionFile = public_path("/{$requisition->acc_document}");
             if ($requisition->acc_document!=null)
            {
                    unlink($requisitionFile);
            }
            $FileName = uniqid() .$request->file('acc_document')->getClientOriginalName();
            $path = $request->file('acc_document')->storeAs('uploads', $FileName , 'public');
            $requisition->acc_document = '/storage/' . $path;
            }
            $requisition->save();

            return response()->json('success', 'Your file has been uploaded successfully.');
        
    }
     }

ajax

<script>
$(document).on('submit', '#FileUploadForm', function (event) {
        event.preventDefault();
        let href = $(this).attr('action');
        var formData = new FormData($('#FileUploadForm')[0]);
      //  let data = $(this).serialize();
        $.ajax({
            url: href,
            method : 'POST',
            data: formData,
            processData: false,
             contentType: false,
            cache: false,
        enctype: 'multipart/form-data',

            dataType: "json",
           headers: {
            'X-CSRF-Token': $('meta[name="csrf_token"]').attr('content')
        },
            beforeSend: function () {
                $('#response').html('<span class="text-primary">Loading response...</span>');
            },
            success: function (response) {
               let data = JSON.stringify(response);
                               alert(data);
            },
            error: function (jqXHR, testStatus, error) {
                alert("Page " + href + " cannot open. Error:" + error);
            },
            timeout: 8000
        });
    });

</script>

form

<form action="{{ route('storefile' , $requisition->id) }}" method="POST"
enctype="multipart/form-data" id="FileUploadForm">
@csrf
<div class="form-group row">
<div class="col-sm-12">

<label for="title"> Account Status: </label>
<select class="form-control" name="acc_status">
    <option value="0" {{ $requisition->acc_status == 0 ? 'selected' : '' }}> Inactive
    </option>
    <option value="1" {{ $requisition->acc_status == 1     ? 'selected' : '' }}> Active
    </option>
    <label for="" id="accstatus"></label>
</select>
</div>
<div class="col-sm-12 pt-4">
<label for="title"> Account document File: </label>
<div>
    @if (!empty($requisition->acc_document))
    <label class="badge-success">
        {{ $requisition->acc_document }}
    </label>
    @else
    <label class="badge-danger">
        Nothing uploaded </label>
    @endif
</div>
<input type="file" name="acc_document" class="form-control" id="acc_document" />
                                    <label for="" id="accdocument"></label>
</div>
</div>
<div class="card-footer">
<div class="row">
<div class="col-md-6 text-left">
    <div id="response">
    <input type="submit" id="submitUpload" value="Upload document"
        class="btn btn-primary">
</div>
</div>
</div>
</div>
</form>

route

Route::post('requisition/{id}/files', [RequisitionController::class, 'storeFile'])->name('storefile');