Return code from JSON to PUBLISHER


I have an aggregate set on publishing incoming data to a JSON server. The publisher is frequently going to ACTIVE_PAUSE, even though it sends the data ahead successfully. Any reason why this happens to frequenty? This is the return code i am sending back to publisher:

        return response()->json([
            "message" => "Success"
        ], 201);

Is this OK, or should I send something else?