Laravel "Malformed UTF-8 characters"

Question

I’m using Laravel in version 5.4 (PHP 5.6) to develop an API.

Recently, when the API was published in Umbler (Linux), when trying to access endpoints that return strings with special characters (more specifically, ã, í) and/or Uuids is released the following Exception

The function of the controller being called is the following:

public function index(Request $request)
    {
         $response = $this->service->get($request->all());

         return response()->json([
             'message' => 'Success',
             'data' => $response['paginated']->getCollection(),
             'next_page' => $response['paginated']->nextPageUrl(),
             'prev_page' => $response['paginated']->previousPageUrl(),
             'current_page' => $response['paginated']->currentPage(),
             'page_count' => $response['paginated']->lastPage(),
         ]);
    }

I tried to use accessors of the Laravel, in the entities to return the data in the following ways:

public function getIdAttribute($value) {
    return utf8_encode(Uuid::import($value)->string);
}

public function getValorAttribute($value) {
    return utf8_encode($value);
}

But the problem persists.

I noticed that when climbing the Builtin Web Server (php artisan serve) on a Windows server the error does not occur, but when using Apache or Nginx, it happens again.

Obs.: On this same Windows server, when adding AddDefaultCharset UTF-8 apache settings, the problem has been fixed, but Ubuntu does not.

Somebody’s had that kind of trouble and they know how to fix it?