troubles with converting byte[] to bitmap (android)

Question

I saw that various people got problems with this. I use retrofit 2.0.0 beta 2 library. In my android application, I want to have a profile picture (so I have actions to upload a new image and to see the profile (with image). My server is ASP.NET Web API.

I've been reading a lot and so far I am able to upload the image (not sure if correctly but it seems that yes). I have problems when I am trying to get the image from the server to display it, I got the answer from the server, but when I am trying to convert bytes array to bitmap i got null result.

Here's my code, u can check it out:

android side (retrofit methods)

@POST("UserProfile/Upload")
Call<ResponseBody> UpdateImage(@Body RequestBody file);

@GET("UserProfile/GetUserImage")
Call<ResponseBody> GetUserImage();

usage of those methods:

private void getProfilePic(){
    Call<ResponseBody> call = service.GetUserImage();
    call.enqueue(new CustomCallback<ResponseBody>(getActivity())
    {
        @Override
        public void onResponse(Response<ResponseBody> response, Retrofit retrofit)
        {
            if (response.isSuccess()) {
                if (response.body() != null) {
                    Bitmap bm = null;
                    try
                    {
                        bm = BitmapFactory.decodeStream(response.body().byteStream());
                    } catch (IOException e)
                    {
                        e.printStackTrace();
                    }
                    profilePic.setImageBitmap(bm);
                    dialog.dismiss();
                } else {
                    // TODO
                }
            } else {
                // TODO
            }
        }
        @Override
        public void onFailure(Throwable t)
        {
            super.onFailure(t);
        }
    });

public void onCropImageClick(View view) {
    Bitmap cropped =  mCropImageView.getCroppedImage(100, 100);
    if (cropped != null)
    {
        showLoadingDialog();
        ByteArrayOutputStream stream = new ByteArrayOutputStream();
        cropped.compress(Bitmap.CompressFormat.PNG, 100, stream);
        byte[] byteArray = stream.toByteArray();

        RequestBody requestBody = RequestBody
                .create(MediaType.parse("application/octet-stream"), byteArray);

        Call<ResponseBody> call = service.UpdateImage(requestBody);

        call.enqueue(new CustomCallback<ResponseBody>(this) {

            @Override
            public void onSuccess(ResponseBody model)
            {
                dialog.dismiss();
                finish();
            }

            @Override
            public void onFailure(Throwable t) {
                super.onFailure(t);
            }
        });
    }
}

web api server side:

    [Authorize]
    [Route("GetUserImage")]
    [HttpGet]
    public async Task<IHttpActionResult> GetUserImage()
    {
        string username = User.Identity.Name;
        Player player = await _service.FindPlayer(username);
        if (player == null)
            return BadRequest();
        return Ok(player.UserImage);
    }

    [Authorize]
    [HttpPost]
    [Route("Upload")]
    public async Task<IHttpActionResult> Upload([NakedBody]byte[] file)
    {
        return await _service.TryUpdateProfilePicture(file, User.Identity.Name) ? (IHttpActionResult)Ok() : BadRequest();
    }

    public async Task<bool> TryUpdateProfilePicture(byte[] file, string username)
    {
        try
        {
                var player = await FindPlayer(username);
                player.UserImage = file;
                _unitOfWork.Save();
                return true;
        }
        catch (DbEntityValidationException e)
        {
            return false;
        }
    }

What I realized: when I am trying to send bitmap (byte[]) to server it returns success and it is stored in database. When I am tryinng to get it from server I got success response and I have some array of bytes but when i try to cast it to bitmap i got null object. Also, as i wrote in the comment section below, when i fetch the bytes from the server I got longer array of bytes than I sent to server, which may be weird, but I don't know.