Flux next() cause poor performance

Question

I am new to reactive programming and I want to implement spring-webclient on our existing project.

For simplicity, I created a pseudo code based from my original code. Here I am sending SMS to each provider. If condition is met then it will not proceed to next provider.

public List<Sms> send(List<Sms> smsRequests) {
    return Flux.fromIterable(smsRequests)
            .flatMap(smsRequest -> {
                return Flux.fromIterable(smsRequest.getProviders())
                        .concatMap(smsProvider -> this.invokeApiUsingWebClient(smsProvider, smsRequest))
                        .filter(providerResponse -> providerResponse.getErrorStatus() == null)
                        .map(ProviderResponse::toSms)
                        .next(); // emits cancel(). Resulting to connection being closed.
            })
            .toStream()
            .collect(Collectors.toList());
}

My problem is that this flow calls cancel() every time next() is invoke. Resulting to poor performance by not reusing the connection on the webclient threads.

See below logs.

TRACE 15112 [reactor-http-nio-1] [ExchangeFunctions] - [5e2f49c] Response 200 OK...
INFO 15112 [reactor-http-nio-1] [1] - onNext(...)
INFO 15112 [reactor-http-nio-1] [1] - cancel()
DEBUG 15112 [reactor-http-nio-1] [ExchangeFunctions] - [5e2f49c] Cancel signal (to close connection)
INFO 15112 [reactor-http-nio-1] [1] - onComplete()

TRACE 15112 [reactor-http-nio-2] [ExchangeFunctions] - [5e2f49c] Response 200 OK...
INFO 15112 [reactor-http-nio-2] [2] - onNext(...)
INFO 15112 [reactor-http-nio-2] [2] - cancel()
DEBUG 15112 [reactor-http-nio-2] [ExchangeFunctions] - [5e2f49c] Cancel signal (to close connection)
INFO 15112 [reactor-http-nio-2] [2] - onComplete()

Is there a possible way to refactor above code without emitting the cancel() method?