WebClient Integration Test with MockWebServer

Question

I dont know if my configuration is wrong or something with mockwebserver. I have method in one of my services

public UserResponse getUsername(String username) {
    return webClient.get()
            .uri("http://user-service/api/user",
                    uriBuilder -> uriBuilder.queryParam("username", username).build())
            .retrieve()
            .bodyToMono(UserResponse.class)
            .block();
}

And I want to test this method by MockWebServer as below

public class CardWebClientTest {
private MockWebServer server;
private CardService service;

@BeforeEach
void setup() {
    server = new MockWebServer();
    WebClient webClient = WebClient.builder().baseUrl(server.url("").toString()).build();
    service = new CardService(webClient);
}

@Test
void test() {
    server.enqueue(new MockResponse().setBody("{\"id\": 12345}")
            .addHeader("Content-Type", "application/json")
            .setResponseCode(200));

    var result = service.getUsername("john");

    assertThat(result.getId()).isEqualTo(12345L);
}

Am I missing something? It's propably something trivial but I can't find solution. CardService which is calling UserService are communicating in EurekaServer with loadbalancer but Im assuming MockWebServer can handle this without any further configuration or not - idk. I will appreciate any help.

UserResponse dto looks like this

public class UserResponse 
private Long id;

I forgot to mention error message. It's always

Failed to resolve 'user-service' after 2 queries ; nested exception is java.net.UnknownHostException: Failed to resolve 'user-service' after 2 queries

Alright. Now I can see that mockwebserver has different hostname - it's calling http://kubernetes.docker.internal:52654/api/user and webclient is asking for http://user-service. But still I dont know how to configure mockwebserver to get response. I should set somehow hostname or maybe leave like that and just test webclient.get() to see if response is correct?