500 Error when setting up swagger in php laravel 5. I provide the correct module reference but it still provides me a 500 Response code

 *
 *    @SWG\Get(
 *      path="/billing/invoice",
 *      tags={"Invoices"},
 *      operationId="getinvoices",
 *      summary="Get all invoices.",
 *      @SWG\Response(
 *          response=200,
 *          description="success",
 *          @SWG\Schema(ref="common/Billing/invoices/Invoice"),
 *      ),
 *      @SWG\Response(
 *          response="default",
 *          description="error",
 *          @SWG\Schema(ref="app/Error"),
 *      ),
 *  )

I'm giving the correct module reference but get 500, 403 and 405 response code.

via Chebli Mohamed