laravel ошибка синтаксиса поиска

      <label for="">Статус</label>
<select class="form-control" name="published">
  @if (isset($category->id))
    <option value="0"@if ($category->published==0) selected=""@endif>Не опубликовано</option>
    <option value="0"@if ($category->published==1) selected=""@endif>Опубликовано</option>
@else
<option value="0">Не опубликовано</option>
<option value="0">Опубликовано</option>
  @endif
</select>
<label for="">Наименование</label>
<input type="text" class="form-control"name="title" placeholder="Заголовок" value="{{ $category->title  ??''}}" required>
<label for="">Slug</label>
<input class="form-control" type="text" name="slug" placeholder="Автоматическая генерация"
value="{{ $category->slug  ??''}}" readonly="">
<label for="">Родительская категория </label>
<select class="form-control" name="parent_id">
  <option value="0">--без родительской категории </option>
  @include('admin.categories.partial.categories',['categories'=>$categories])
</select>
<hr>
<input class="btn btn-primary" type="submit"  value="Сохранить">

сама ошибка

syntax error, unexpected '??' (T_COALESCE) (View: /home/alexcc/LaravelBlog/blog/resources/views/admin/categories/partial/form.blade.php) (View: /home/alexcc/LaravelBlog/blog/resources/views/admin/categories/partial/form.blade.php)