C# не работает Wiremock.net

Вот мой wiremock

        _wireMockServer
            .Given(Request.Create().WithPath("/auth/admin/realms/FirstLink/groups?first=0&max=100")
            .WithHeader("Authorization", $"Bearer {testToken.Token}")
            .UsingGet())
                .RespondWith(
                    Response.Create().WithBodyAsJson(new List<Group> { testRequiredGroup })
                        .WithStatusCode(HttpStatusCode.OK));

И вот где она вызывается

public async Task<ICollection<Group>> GetAllGroupsAsync(CancellationToken cancellationToken)
    {
        _httpClient = await AuthAsync(_httpClient, _keycloakOptions.Realms, cancellationToken);
        var skip = Skip;
        var result = new List<Group>();

        do
        {
            using var response = await _httpClient.GetAsync(
            $"/auth/admin/realms/{_keycloakOptions.Realms}/groups?first={skip}&max={Take}",
            cancellationToken);

            var responseJson = await response.Content.ReadAsStringAsync(cancellationToken);
            var responseObject = JsonConvert.DeserializeObject<ICollection<Group>>(responseJson);

            if (responseObject.Count == 0)
            {
                break;
            }

            result.AddRange(responseObject);
            skip += Take;
        }
        while (true);

        return result;
    }

Но в итоге ошибка