Rejecting additional inbound receiver

Question

I have a Feign client, which is web Reactive Feign, there is a method as responseMapper, which is implementing ReactiveHttpResponseMapper<Publisher<?>>. In the apply method, I need to bring out a byte array and return the original response. But is failed with Rejecting additional inbound receiver. State=\[terminated=false, cancelled=false, pending=0, error=false\].

Here is my code snip:

---

@Bean
public SabreClient sabreServiceClient () {
    return WebReactiveFeign.<SabreClient>builder(webClient().mutate())
        .options(new WebReactiveOptions.Builder().setConnectTimeoutMillis(config.getConnectTimeOut())
            .setReadTimeoutMillis(config.getReadTimeOut())
            .setWriteTimeoutMillis(config.getWriteTimeOut())
            .setResponseTimeoutMillis(config.getResponseTimeOut()).build())
        .addRequestInterceptor(ReactiveHttpRequestInterceptors.addHeader("Cache-Control", "no-cache"))
        .addRequestInterceptor(new SabreClientInterceptor(config, loginClient))
        .responseMapper(new ResponseMapper())
        .target(SabreClient.class, config.getApi());
}

---

@Log4j2
public class ResponseMapper implements ReactiveHttpResponseMapper<Publisher<?>> {

    @Override
    public Mono<ReactiveHttpResponse<Publisher<?>>> apply(ReactiveHttpResponse<Publisher<?>> response) {
        response.bodyData()
            .doOnNext(bytes-> log.info("Received data: {}", new String(bytes)))
            .subscribe();
        return Mono.just(response);
    }
}

I want to receive a String from bytes for some DB stuff and return the original response. Please help me.