Refit package 502 Bad Gateway error in .Net Core when calling other API

Question

I am getting a strange error when calling an API from other API using Refit library.

FYI: My APIs are built using .Net 5.

The First API returns 200 response it is just the Refit which is unable to show the response.

I have checked the types of the response and model which are compatible.

First API

The declaration of the endpoint:

    [Get("/projects/private/list")]
    [Headers("Authorization: Bearer")]
    Task<List<ProjectsResponse>> GetProjects([Body] ProjectsRequest projectIds);

The definition:

    [HttpGet("private/list")]
    [ProducesResponseType(statusCode: (int)HttpStatusCode.OK, type: typeof(IEnumerable<ProjectsResponse>))]
    public async Task<IActionResult> GetProjects([FromBody] ProjectsRequest request)
    {
        IEnumerable<Project> projects = await _mediator.Send(new GetProjectsQuery { ProjectIds = request.ProjectIds });

        return Ok(_mapper.Map<List<ProjectsResponse>>(projects));
    }

The request model:

public class ProjectsRequest
{
    public string[] ProjectIds { get; set; }
}

The response model:

public class ProjectsResponse
{
    public string Id { get; set; }
    public string Name { get; set; }
}

Second API

The call:

List<ProjectsResponse> projects = await _otherApi.GetProjects(new ProjectsRequest
            {
                ProjectIds = projectIds.ToArray()
            });

Basically I am returning list of objects in the response which is causing this problem.

The strange behavior is that when I log the Request.Content it works fine but when the log is removed the 502 error starts popping.

So, when I add _logger.LogInformation("Request:{data}", await request.Content.ReadAsStringAsync()); everything works correctly but when it is removed the Refit starts throwing 502.

I have done the token handling using the DelegatingHandler of the Refit.

protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
    {
        try
        {
            var token = await GetAccessTokenAsync();

            request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);

            //_logger.LogInformation("Request:{data}", await request.Content.ReadAsStringAsync());//Uncommenting this line makes it work.

            HttpResponseMessage httpResponseMessage = await base.SendAsync(request, cancellationToken).ConfigureAwait(false);

            //_logger.LogInformation("Response:{data}", await httpResponseMessage.Content.ReadAsStringAsync());

            return httpResponseMessage;
        }
        catch (ApiException ex)
        {
            _logger.LogError(ex, ex.Message);
            throw;
        }
    }