Java.Net.ProtocolException: unexpected end of stream when trying to upload file as a byte stream

I have an image file that I am trying to upload to a database using a http API. every time I try uploading I get the same error:

[monodroid] Not wrapping exception of type Java.Net.ProtocolException from method `Read`. This will change in a future release.
unexpected end of stream

Here is my code

using GT_MI.API;
using System;
using System.Collections.Generic;
using System.IO;
using System.Net.Http.Headers;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;
using Newtonsoft.Json;

namespace ShorelogApp.API.Misc
{

    public class SaveSeas : ApiBase<RequestBase, SaveSeas.Response>
    {

        public class Response : ResponseBase
        {
            public string Path { get; set; }
            public string FileName { get; set; }
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="file">Byte array representing binary encoded file</param>
        /// <returns></returns>
        public async Task<Response> SaveFileAsync(byte[] file)
        {
            HttpResponseMessage httpResponseMessage = null;

            try
            {
                // Construct the HttpClient and Uri, with a timeout of 16 seconds
                var httpClient = new HttpClient()
                {

                    Timeout = TimeSpan.FromSeconds(16)
                };

                var uri = new Uri($"{ApiManager.BaseUrl}/seas/save_seas");
                Debug.WriteLine($"URL: {uri.AbsoluteUri}");

                if (string.IsNullOrEmpty(ApiManager.Token) == false)
                {
                    Debug.WriteLine($"[Token]: {ApiManager.Token}");
                    httpClient.DefaultRequestHeaders.Add("token", ApiManager.Token);
                }
                
                // using byte array content type
                ByteArrayContent content = new ByteArrayContent(file);
                content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream"); //"application/octet-stream"
                content.Headers.ContentLength = file.Length;
                httpResponseMessage = await httpClient.PostAsync(uri, content);
                
                
                httpResponseMessage.EnsureSuccessStatusCode();
                var httpResponseBody = await httpResponseMessage.Content.ReadAsStringAsync();
                Debug.WriteLine($"Response Data: {httpResponseBody}");

                var resultJson = JsonConvert.DeserializeObject<Response>(httpResponseBody, jsonSerializerSettings);

                Debug.WriteLine($"Response Json:\n{JsonConvert.SerializeObject(resultJson, Formatting.Indented)}");

                return resultJson;
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                return HandleException(httpResponseMessage, ex);
            }
        }
    }
}

I have tried adding a content header with the size of the file, as I read that sometimes this error is caused by the request body being recognised as the wrong size on the backend, but it didn't work
I tried compressing the file before uploading it, as I thought it might just be too big, but that didn't work.
I tried uploading the file as a string through JSON and uploading it as a ByteArrayContent type, but I always get the same error.

I got it working, by changing the httpContent type to a MultipartFormDataContent it worked, so the request now looks like

                MultipartFormDataContent content = new MultipartFormDataContent();

                ByteArrayContent fileContent = new ByteArrayContent(file);
                fileContent.Headers.ContentType = new MediaTypeHeaderValue("image/png");
                content.Add(fileContent, "file");
                //ByteArrayContent content = new ByteArrayContent(file);

                httpResponseMessage = await httpClient.PostAsync(uri, content);

This gets past the end of stream error.