private function makeNotFoundResponse(Request $request): Promise {
        return $this->errorHandler->handleError(Status::NOT_FOUND, null, $request);
    }
private function makeNotFoundResponse(Request $request): Promise {
        return $this->errorHandler->handleError(Status::NOT_FOUND, null, $request);
    }
private function makeNotFoundResponse ( Request $ request ) : Promise { return $ this -> errorHandler -> handleError ( Status :: NOT_FOUND , null , $ request ) ; }
Create a response if no routes matched and no fallback has been set.

@param Request $request

@return Promise<\Amp\Http\Server\Response>
Create a response if no routes matched and no fallback has been set .