How do I send large data files using HttpClient.PostAsync? [duplicate]

My function is below. It works just great with anything up to around 25MB, but greater than that and it stops working. When I say stops working, it throws no exceptions and fails to the noserver result option at the bottom of the function. I can't seem to find any settings referring to any other buffer size though I found some Microsoft Documentation which does say the response buffer is 2GB default.

Any ideas, any help would be appreciated.

• VS2019 ASP.NET
• 4.7.2

• Winforms

  public async Task<JsonApiResult> GetHttpData(string Message, string serviceMethod)
  {
      System.Diagnostics.Debug.Print($"{serviceMethod}{Message}");
  
      HttpClient _httpClient = new HttpClient();
  
      _httpClient.DefaultRequestHeaders.Accept.Clear();
      _httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
      _httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/text"));
  
      _httpClient.BaseAddress = new Uri(_url);
  
      try
      {
          //////
          StringContent payload = new StringContent(Message, Encoding.UTF8, "application/json");
  
          HttpResponseMessage getResponse = await _httpClient.PostAsync(serviceMethod, payload);
  
          if (getResponse.IsSuccessStatusCode)
          {
              try
              {
                  var response = getResponse.Content.ReadAsStringAsync().Result;
  
                  JsonApiResult result = JsonConvert.DeserializeObject<JsonApiResult>(response);
  
                  return result;
              }
              catch (Exception e)
              {
                  return new JsonApiResult { Result = "fail", Message = e.Message, Data = "" };
              }
          }
          else
          {
              //<<<<<<<<<<<<<<<<<<<<<<<<<
              return new JsonApiResult { Result = "fail", Message = getResponse.StatusCode.ToString(), Data = "" };
          }
      }
      catch (Exception e)
      {
          return new JsonApiResult { Result = "errserver", Message = e.Message, Data = "" };
      }
  
      return new JsonApiResult { Result = "noserver", Message = "Could not connect to server", Data = "" };
  }
  

On the server-side I'm using

    public async Task<JsonApiResult> GetMyFileUploads([FromBody]JsonApiResult result)
    {
    ...